I was 16 when I began to see 30 as a landmark year. By that point I should: 1) Have a career. 2) Have found Mr Right. 3) Pocketed £1m. 4) Travelled to exotic, far-flung locations in the name of love. 5) Own a splendid house with Mr Right, who is on his way to being Mr Husband and can pause for a cup of tea just as soon as he has finished fitting the new granite kitchen worktops.

None of which happened. It was a completely self-imposed delusion, a madness that was no doubt brought on by an overconsumption of magazine articles about lasting relationships, how to have great sex and demand the orgasm you deserve, while having the career you want, the commitment you desire and visiting the best places on earth, all by the time you turn 30. My personal goals were planted in my manic head like a red stick of dynamite by Wile E Coyote. If I didn’t achieve all this by 30, I imagined an anvil would fall from the sky and ram me into the ground.

I didn’t have a plan for bagging the million pounds: life as a Hollywood prostitute was one option, winning the Littlewoods pools another. When the national lottery was launched, that really broadened my horizons. I came from a respectable working-class background. The era was pre The Apprentice and education was everything to me: take a bite, it urged, and you’ll grow big. Hadn’t I worked hard to get to grammar school and then to university? It’d be a cinch.

My twenties were going to be such fun. Maybe I would neck tequila as a holiday rep in Ibiza, then go to university, then travel to India in search of enlightenment. I reckoned that at 28 I’d morph into a Good Woman. This would coincide with the year Mr Right would drift to me atop a cloud, and I’d plan my wedding. Until that point, I would be free to play.

I didn’t bargain on falling pregnant at 19, fleeing my lovely house because of a difficult boyfriend, struggling through university as a single mother and living on a council estate. At 22, I was temporarily homeless with a toddler, and an emotional wreck. I couldn’t even provide stability for my son. I was frightened of my ex-boyfriend, troubled, and riddled with guilt that I’d let down my parents. I limped through my degree gaining a respectable 2:1, then began an MA in novel writing. I had expected opportunity, happiness and love to make up the fabric of my early twenties as I swept towards stability and comfort in my thirties; mostly I felt as if I was swimming through a river of mud. At 25, I started working for City Life magazine in Manchester. Gradually my life melded back together. I wasn’t searching, but remained optimistic that I’d find my one true love.

What a fantasist. When men approached me in bars, I felt as if I should have been taken to court under the Trade Descriptions Act for touting fake goods. I recognised men’s disappointment when faced with the reality; it was similar to when my mother bought me Nicks trainers because she thought they were Nikes.

I fell for men who didn’t want me, or men fell for me and couldn’t handle the responsibility of a child, or they were charmed by my son and wanted to save me from the mess they thought I’d landed myself in — but I didn’t love them. It was a very unlucky mixture, which I reckoned would become clearer as I approached 30. I so desperately wanted to provide a happy home for my son.

I met my almost Mr Right when I was 26. He was working in television and arrived on a cloud, along with big plans to earn £80,000 a year. Brilliant. He was also a rugged, outdoor kind of guy. Smashing. He wrapped us in love like a fluffy blanket and I cosied myself into him. Hurrah! I thought I had it right at last.

Or not. He didn’t believe in monogamy, then he became anticapitalist, so the £80,000 a year went out the door. As a vegan environmental activist, he wasn’t interested in buying a house or granite worktops, and he wouldn’t fly, so that was the end of exotic locations in the name of love. He proclaimed to be anti-institution, so that was marriage and more kids out of the window. But I loved him regardless.

Years passed. I edged closer to 30. I became plumper. My hair gradually turned from glossy brown to salt and pepper. I watched the scene in Sex and the City where Samantha “dyes her bush” for handy hints rather than hilarity. My arms, once my best feature, thickened. I was patching an income together from freelance journalism and PR. The hours were long and the money poor. Early mornings and evenings, as my son slept, I wrote short stories, plays and, for a bit of light relief, a blog charting it all, called Single Mother on the Verge. I began to wash the dishes with the same posture as my now dead grandmother. I thought, this is why 30 is such a landmark — it’s all anti-ageing cream recommendations and, after that, horror stories about painful periods.

When I reached 29, redundancies were the new craze. I lost a job at an arts magazine and I didn’t have any new projects in the pipeline. A month before I turned 30, I wasn’t even close to being a grown-up — despite being a mum. My life resembled one of those perfumes I made as a child by mixing shampoo, rose petals and orange juice together in the hope it would smell beautiful. My dream of being sorted by 30 looked futile. My relationship with the vegan was doomed and I hadn’t even travelled to an exotic location on holiday.

In the months leading up to my birthday, it began to dawn on me that if I didn’t want my thirties to be like my twenties, I needed to ask the men in my life difficult questions such as, do you love me? Do you want children? Do you see yourself married to me? I suspected that the answers to those questions would be no, no, no.

Quite true. On the cusp of 30, I found myself single again. It was liberating to make the decision not to have awkward boyfriends, casual flings or comfort sex. I started to see 30 not so much as a deadline for a project I had failed, but more as a watershed: a border that I needed to cross to get to a better place. I could bend my own rules. I had thought men were the solution, but I was wrong. I realised that being courageous in my own decisions would bring about the changes in my life that I craved.

A month before my birthday, on a whim I sent a hopeful e-mail to a literary agent. Two weeks later he had secured me a book deal. The following summer I left Manchester. Now I live with other single parents and their children in a communal house in London. It’s zany, but I like it.

Now I’m 31, my rear end has much in common with the back of a Fiat Punto, so hopefully one day I’ll find a man with a fetish for Italian cars. I love not being in my twenties. I’m so much happier because I am content with where I am in my life: a single mother to a kind, handsome, intelligent 10-year-old-boy — at least I succeeded there. I am transitory and hopeful and I no longer feel compelled to force my life into the direction I think it should go. Well, for now. As a masochistic creature of habit, I’ve set 40 as my new landmark — which gives me six-and-a-half worry-free years, before I have the last two neurotic ones. 

Single Mother on the Verge (Penguin £6.99) is out on Thursday

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