“We’re going to have to disconnect you,” says the man at my bedside. Since I was hospitalised a fortnight ago, this man and his team have been trying to save my colon, a 5ft-long tangle of ulcers and inflammation. The speed and scale of my colon’s fury has fascinated doctors. I imagine them in their morning meetings, poring over my colonoscopy with the mystification usually reserved for the Voynich manuscript. But time is up. Unless they “disconnect” me, my bowel will perforate and I will die.

Disconnection, explains the doctor, involves whipping the whole colon out – here he mimes pulling a rabbit from a hat – and diverting my digestion through a hole in my abdomen called a stoma. He sketches my new anatomy on a piece of paper, quick as a high-street caricaturist. He cannot imagine what it is like to receive this news – to hear your body will change for ever and with it your whole life too – just as I cannot imagine what it is to break it. I want to grab his hand, ask him how. How does a body give birth to a healthy baby and then burst into flames?

I hadn’t planned to be living with my parents when I became a mother, but that’s what happens. My boyfriend, Will, and I have bought a fixer-upper whose every wall, floor and ceiling is, according to my dad, “completely pissed”. The latest in a long line of house-building Irishmen, he sets about restoring its broken bones for us with surgical skill. Meanwhile, Will and I Zipvan our lives back to the London suburb I snubbed aged 21. Now, up the duff at 35, I’m won over by it all – the quiet, the Costa Coffees, the middle-aged blokes reverently soaping their Qashqais. I feel unbelievably lucky to have this time with my mum and dad, this last gulp of being someone’s kid before I become someone’s mum.

I am invited for extra scans, having been classified as “high-risk”. “Because I’m 35 and ‘geriatric’?” I ask one consultant. “No,” she says. “Because of your Crohn’s.” I was diagnosed with the inflammatory bowel disease as a teenager. I don’t remember much, besides a few missed school trips and the dark thrill of no longer being the chubby one in my group of friends. I’ve had no symptoms since. “All looks fine!” beams the sonographer. The baby bobs under the ultrasound wand. It’s the only time my disease history is mentioned.

My son is lifted out of me one Sunday in early July, as Joan Armatrading’s Love and Affection blasts from the delivery-room speakers. Navy-eyed and howling, he is totally alien and powerfully familiar to me all at once. We bring him back to my parents’ house where my brother’s old bedroom is ready for us, shelves of school cricket trophies now stuffed with bottles, muslins, nipple cream. We swaddle the baby the way the midwife showed us – tightly, like a tiny nativity play shepherd – and cannot believe our luck.

I begin to feel porous. Leaking boobs, but other things too: sweat-drenched bedsheets, grinding pain, violent splashes of blood in the toilet. Even the smell of my own breast milk sends me running to the bathroom. I am determined to keep pumping, recording diminishing quantities on my phone: 40ml left boob, 30ml right boob. The baby screams, unsatisfied. I promised I’d go easy on myself if breastfeeding didn’t work out, but now the desire to feed him myself is fierce, irrational, like I need to beat whatever is eating me from the inside out.

When I describe how bad things got before I sought help, people assume I was trying to be invincible. They are thinking, perhaps, of those apocryphal women who lift cars off their young, oblivious to pain. But I’m acutely aware of my pain, I’m just unsure what it means. A suspicion takes hold that I am not tough enough for motherhood. For the sleeplessness, nursing, the magnificent horror of being sliced open.

Unable to get a GP appointment, I pay to see a private doctor, a kind-faced man retired from the NHS. I say I think childbirth has reactivated my Crohn’s. Unlikely, he says. Caesareans famously make the bowels grumpy. He prescribes antibiotics which I immediately throw up. Will drives me to A&E, where the triage doctor calls me “honey”, asks how bad the pain is on a scale of one to ten. Six? Ten? I don’t know the metric. Motherhood has made me an unreliable narrator of my own body. It’s almost a relief when, one morning, delirious with pain, I collapse. At least now there is no ambiguity, I think hazily. As paramedics wheel me out, the baby starts to cry and my mum dashes inside to change his nappy. I do not get to kiss him goodbye.

In TV medical dramas, the patients usually only feature in one episode and then they either get discharged or die. There is a rule that predicts their fate. Demanding patients suffer the most, because they need to be humbled and learn not to be a dick. Sweet, quiet patients – the ones who never press the call bell too often – die first. I hedge my bets and go for “friendly but forthright” in the hope I will make it out alive when the credits roll.

Having never been hospitalised before, there is an initial thrill in observing this ecosystem up close, with its otherworldly machines, bleeps, tourniquets. I am a tourist, just stopping by while the doctors work their magic, then I will step out of this hospital drama, back to my four-week old baby.

I spend the first day on a corridor containing so many patients that staff call it the “Corridor ward”, as if Mr Corridor is a trailblazing scientist. Since there is no space on the gastro ward, I am shipped to an A&E overspill area, where I join the miscellaneously broken. On the bay opposite are two elderly drunks who wind everyone up by singing the same three Beatles songs. Next door is a prisoner with an infected leg who threatens anyone who comes near with legal action. The nurses are kind and visibly stressed. The whole place thrums with the panic of a Panorama documentary, a sensation heightened by the steroids flooding my body.

After a colonoscopy reveals my flaming insides in psychedelic detail, I am diagnosed with severe ulcerative colitis. They will later conclude that my teenage Crohn’s diagnosis was erroneous. The idea is that the gastro doctors will visit me on the A&E ward, but after five days I’ve seen a consultant once. I cannot work out who to badger; it feels like all the people who can help me are elsewhere. A junior doctor mutters that the gastro ward should be renamed the Glasto ward: “That’s how impossible it is to get a ticket.” If only I could chuck on a bucket hat, scale the perimeter wall.

My confidence that I will make a Lazarine recovery falters, chipped away by the tedium of 30 toilet trips a day. I must chronicle them on a daily worksheet, a humiliation compounded by the Comic Sans font. Nevertheless, it sparks a nerdy satisfaction. I add an elaborate asterisk system to denote cramps, spasms, blood. I take it very seriously until the day I hand it in and watch the ward sister shove it straight in the bin.

We decide it’s not safe to bring the baby inside the hospital, as he hasn’t had his jabs yet. So, on the days I can get up, Will brings him to the car park or the garden. My arms are so weak that I’m scared to hold him. Will shows me new winding techniques his mum’s taught him, videos of his dad bathing the baby in the kitchen sink. Some days we laugh a lot. On others, our conversation is a careful dance, each trying to conceal the fullness of our sadness from the other.

Will and the baby are living out of a suitcase between our parents’ homes. I wait for the nightfeeds – midnight, 3am, 6am – when Will sends sleepy voice memos, the baby guzzling in the background. We should be doing this together, sharing the exhaustion and the dirty nappies, the magic chaos of it all. None of us are in the right place. “Has he smiled yet?” I ask. “If I miss his first smile, don’t not tell me.” The baby is changing fast, learning about the world somewhere I am not. This is the unbearable ache, the stone I cannot swallow.

I feel myself crossing over into what Susan Sontag called “the nightside of life”. I’m unable to recognise my own moonface, eyes hollow with insomnia. The kingdom of the sick is where I belong now and it’s no picnic for a people-pleaser. “I’m keeping my pecker up” becomes my party line, like a politician on a media round. But I can see the black puddle of despair in the corner of my room. I am scared to go near in case the questions come (Why me?) and I fall in.

I begin to absent myself from my body. The phlebotomist’s catchphrase comes twice a day – “Sharp scratch” – but I feel nothing when the needle goes in. In the middle of the night, I read about the plan to put people on planes to Rwanda, a newsreader’s sex scandal – things that would normally stir me. But they feel like missives from a universe I don’t exist in any more, so what’s the point? Sickness confirms my impotence to do anything about anything. The world is on fire and so is my body and nothing can be done.

After a weekend passes with no consultant visit, I find the private doctor’s email on his personal website. I say I’ve been diagnosed with severe ulcerative colitis and I’m getting worse. I feel a bit ridiculous, like one of those people who tweet Michael O’Leary for a refund on their Ryanair flight. What can he do, this man? He can’t invent beds on the gastro ward, nor time-travel me through to Monday morning when the consultants will be back. He is literally, according to his out-of-office autoreply, on a walking holiday in Norfolk.

He calls immediately. Apparently I am at risk of developing a very straight-to-DVD-sounding condition called “toxic megacolon” where the whole thing bursts. I need to be on immunosuppressant therapy immediately, he says. And something else: “85% of patients in your position end up needing a colectomy.” What is that? I ask. “The bowel is removed and the patient fitted with a stoma,” he says. “The last resort.”

Like you perhaps, what comes to mind is a bag of waste stuck to a stomach. That’s the visual, that’s the extent of my prior knowledge. I know it must cover something – the “stoma” presumably – but I have no interest in that. Because it will not, cannot be me.

The private gastro pulls the emergency lever all the way from the Norfolk Broads. He used to work here in his NHS days, it turns out. Consultants are paged, the immunosuppressant arrives. But it can only be administered by a specific nurse whose shift ends within the hour. A side-room frees up on the gastro ward, but due to staff shortage it has not been cleaned, so I cannot be transferred. My dad – straight off the scaffold, hair full of plaster dust – runs to find the ward sister. “I will clean that room”, he says, in a low voice that I know means he’s scared. My poor, lovely dad. “Please let me clean it.” Soon I am wheeled to a room on the right ward, hooked up to the new drug. “At last!” we all keep saying, as if that was the worst bit. But over the next fortnight, I will discover there is no limit to how terrifying things can get.

There’s the moment I realise no one has accessed my test results for days because the junior doctors are striking and the consultants don’t know how to log on. The evening an unsympathetic registrar tries to throw me out of my room, claiming a palliative patient has greater need. (I later discover this is a fiction: one of the alcoholic Beatles fans is proving too disruptive.) The moment a trainee stoma nurse tries to draw an X on my stomach where a stoma would go, despite no doctor having made the final call on surgery yet, despite me crying “No, please, I’m not ready.”

There’s the nurse who forgets to warn me she’s about to pull a thick tube from inside my belly (agony!) because she is so stressed, trying to teach junior nurses. The day I’m so desperate to see a psychiatrist about my hallucinations that I try to bribe a millennial female doctor with a Facetime from my bestselling author mate to make it happen. (I’d been asking for a week.) The rage when I discover on a late-night Google trawl that “one in three women with inflammatory bowel disease will flare after giving birth” and “women with IBD should be closely monitored postpartum.” How did I not know? Why did no one tell me?

But there are no villains in this story, I know that now. Just people under huge pressure, in an overstretched, underfunded system that doesn’t work any more, doing their best. And there’s no magic medicine, I know that too. Just good luck and bad luck as to whether the drugs will work, save your colon, save your life, save you from the surgery you think will ruin everything. It’s all luck in the end. And my good luck begins the night three brilliant surgeons walk into my room and promise me a stoma is going to give me my life back and I decide to believe them.

I really have no other choice.

I wake up from the eight-hour operation in what appears to be a large industrial storage unit. No free beds on the recovery ward. Something strange surges in me. I feel stuffed full of love for the earth and all of its creatures. I am the Dalai Lama. I am John and Yoko’s bed!

“Is this the fentanyl?” I ask my surgeon, wondering if he’ll let me hold his hand. “Maybe,” he says. “Or you might just be happy to be alive.” I have questions. Who owns my colon now? “Nobody. It’s biological waste.” Where is my colon, exactly? “A lab in Winnersh Triangle.” This sends me into hysterics. I’ve finally cracked, I think.

I don’t want to ruin the lovely opioid high by looking under the sheets, but the nurse says I can’t be discharged until I prove I can deal with the stoma. So I take a deep breath, pull up my gown.

Most people are too polite to ask what a stoma looks like. Their imagination cuts out at the bag, the way mine used to. But the bag is just the figleaf: the madness is what it conceals. The common assumption is a little tube, discreetly passing waste from body to bag, like a tiny hoover. This is cute, but wrong.

Here’s what I can see. A red spout, 3cm across, protruding between my navel and hip. The end of my small intestine, I realise numbly. Covered with a clear bag for monitoring, it flexes and scrunches like a sea urchin. It feels appalling and amazing to see what I can see, this most private and shameful process brought into daylight. It seems improbable that it should actually work – the bag seems so DIY – but I eat a jacket potato and feel the thing murmur into action.

There’s so much paraphernalia to get my head around: bags, seals, sprays, powders. It’s like I’ve taken up a hobby with a dizzying amount of kit, like vaping or golf. “Some people give their stoma a name,” says the nurse, “to help them accept it.” No chance, I think. It’s not a Tamagotchi, it’s my intestine for god’s sake.

I imagine stepping back into my old life now. Teaching, writing, pubs, gigs, sex, holidays. How could I forget for long enough to enjoy anything? It hits me that no one I know would want to have this body – a very particular kind of loneliness.

The doctors love a metaphor. They refer to my plumbing. Pipework. Shuddering, loveless imagery that recalls our fixer-upper, with its wretched old drains. But their favourite metaphor is “disconnected”. I see it in a letter to my GP: “The patient was disconnected on 18 August.” It’s a good metaphor, maybe too good. It’s not only my bowel that has been disconnected, but me too. From everyone I love. From my old innocence, whoever I used to be.

After Will calls to say he is on his way to visit, I try to rejig my bedsheets. A healthcare assistant called Hassan comes by and I’m suddenly in tears. I don’t want Will to be scared by the drains ferrying awful liquids from my body, I explain. Hassan leaves and returns with a pot of raspberry jelly. “You are feeling shame for what happened to you,” he says gently. “But it’s not your fault.”

No doctor has been able to tell me why having a baby made my body burst into flames. I am all arson with no perpetrator. In the absence of a culprit, I have cast myself. What if I had known more about inflammatory bowel disease? What if I had eaten differently, given birth differently, got myself to hospital quicker? Could things have fallen out some other way?

Hassan’s words reach out to me in the dark. I do some more crying, eat the jelly he has brought me.

It is late summer by the time they discharge me. It feels like a jailbreak. Will and I roll down the car windows, sing along to Rusted Root’s Send Me on My Way. My parents are waiting on the doorstep with the baby – eight weeks old now, plump as a peach. I’ve been away half his lifetime.

The doctors warned my mood would crash when the drugs wore off. I wait for the black puddle to turn tidal. Instead, I find illness has shifted the world by a few centimetres. Jokes are funnier, conversations more sincere. Everyday things feel like unbelievable acts of magic. Cooking dinner with my mum. Making up a song for the baby. Life hums with a kind of Technicolor, like falling in love. My opioid high has mellowed into something as warm and steady as the September sunshine. The surgeon was right: I am just so happy to be alive.

I had planned to tell only those closest to me about my stoma. But at some point I realise that discretion’s closest relative is shame and cannot stop talking. I pick up a sandwich from the Jewish deli and am there half an hour, telling the bewildered owner about my exploding colon. I develop a pathological intolerance for pleasantries. Will starts calling me the Truthbomber on account of my tendency to blow up pointless small talk. Friends visit and I gibber away, pulling stories from my ragbag of hospital traumas, prone on the sofa like Elizabeth Barrett Browning on speed. I write long emails about what happened to family, friends, colleagues, finding release in the way I can control its contours now, find something meaningful in the darkness.

In the quiet of the bathroom, I shower and dodge the mirror’s gaze. The baby trills happily in his bouncer, unaware I bring him along for moral support every morning as I tend to my stoma, change the bag. He’ll never know me any other way than this. I need to face my new punctured body, still stained with orange surgical dye. Unwire all of my shame, old and new. I want to learn to look at myself the way the baby does – with uncomplicated, uncritical love.

I try to think of my body as a collection of stories. The freckles inherited from my mum. The scar from a pair of GHD straighteners on my neck, ultimate badge of early noughties girlhood. The queen of hearts tattoo on my wrist my best mate and I got two summers ago. The curve of a belly that kept the baby safe, the five-inch cut where he was prised from me. The laparoscopic holes, incredible portals through which surgeons cut five feet of disease. I think of my body as an old friend I have lived in for 35 years. And though I no longer trust it, I cannot hate it.

When winter comes, we move into our house and throw a party. We lug beer back from the Wembley Tesco Extra, pick up a firepit in B&Q. At some point, I realise I want to make a speech about Will. About the way he’s held me fast, his love unflinching. “We’ve been together six years,” I tell everyone. “But you know how the old adage goes. You never really know a man till your colon explodes.” Our friend Adam gamely conducts a shamanic ritual over the firepit in the garden, wearing a pagan hood off Amazon. We huddle in the cold, pass round Biros, scribble down the worst things that have happened to us, cast them into the flames. A friend brings a piñata emblazoned with “Fuck 2023” which I take great pleasure in thwumping. Surrounded by everyone I love, I feel the threads between my old and new selves begin to reconnect.

The first year of a baby’s life is peppered with milestone moments, not all of them showstoppers. Many happen without ceremony, as you stoop to unload the dishwasher, fish a stone from your shoe. Sometimes there is no “first” time at all, just a seamless switch from nothing to something. The baby’s first smile comes a few days after I get out of hospital. Just the corners of his mouth, then an unmistakable full beam. I had been so convinced I’d miss it. “He saved it till you got home,” says my nan.

I’ve become aware of all my firsts too, since illness split me into a before and after. First time in a swimming pool. First Christmas. It’s been a long time since I got to do things for the first time. I watch the baby’s face flood with shock and delight as he collides with the world. First ride on a double decker. First taste of pineapple. One day, I’ll tell him how he saved me. How, in the moments that I replay the darkness, his little face pulls me back to the present. I’ll tell him how much he taught me in our first year together. Eyes wide open, looking at the big bright world, both of us brand new.