My proudest achievement by far is learning to drive, aged 37. I often still marvel at myself, changing the gears with one hand. I feel very empowered and really very, very pleased with myself.

When I was two, my mother’s chip pan caught fire – and that’s how religion started for me. She’d taken down a plate from the wall that had a prayer on it; I linked the fire to us interfering with God’s word. Today, I despise organised religion – they’re all misogynistic, they’re all about keeping people terrified, controlling women. Catholicism is obsessed with people’s sex lives. Having been brought up with it, fear and shame are still my core emotions.

I was a nihilist from an early age. I only studied law because I got the grades – I never had any sense of a future. When I graduated I became a waitress.

People ask when I became an alcoholic. But I was born that way. My great friend alcohol was the thing that enabled me to function and pass myself off as normal. But it was like standing on an island that was getting smaller and smaller. Everyone around me was getting married and having babies and buying carpets and then buying curtains that match the carpet – and I was still drinking. I felt more and more suicidal. Then, one afternoon in the September of ‘93, I read a short story and thought, I could write something like that. And I did.

Depression feels like extreme disconnection, like I don’t love anyone and nobody loves me. The fear feels like something catastrophic has happened, even when it hasn’t. When it comes now, I tell myself I’ve been through much worse. I bargain with myself. I stop, and reduce life to simplicity as much as possible.

When my dad died a year ago, I mainlined Mills & Boon. It’s the absolute escape from my sorrow. I know nothing’s going to jump out and scare me. And this has been very good for me – I have no right to judge what anyone reads or watches on telly. You know, we’re all doing our best. We’re all trying to get through.

I wanted to write books about women who struggled. But slapping a demeaning label on those books, “chick-lit”, sticking a pink glittery shoe and bottle of prosecco on the cover, immediately divested them of power. When you shame people for what they read, you take away their confidence in other areas as well. This was more than just literary snobbery, it was an attempt to keep feminism out of politics.

At 56, I get courage from young women. During the abortion referendum here in Ireland I campaigned for women’s rights to bodily integrity with my 19-year-old niece who is fearless, intelligent and articulate about feminism. Young feminists are fighting the war and I want to be in their army.

In Ireland we’ve a huge homelessness problem and our health system is not fit for purpose. I like being generous, but I would prefer if it was more formalised. I would be really happy to pay much higher tax to take care of the vulnerable.

I got hair extensions on my 56th birthday. And I think they’re fabulous. I’m not cutting my hair into a cauliflower helmet to be age-appropriate. And if people look at me and say, “Jesus, Who does she think she is?” I don’t care.

I love getting older. I was lost and clueless for so long, waiting for other people to tell me who I should be. I am wiser now, and I know life is painful. But it’s survivable. I always thought 53 would be a great age. Now I’m thinking maybe 68 will be even better.

Grown Ups by Marian Keyes (Michael Joseph, £20) is published on 6 February. Buy a copy for £17.60 at guardianbookshop.com