Catherine Townsend: Sleeping Around

I had a nasty shock a few days ago. There I was, shopping for the perfect outfit for my first date with Ross, when I ran into my ex-boyfriend Paul outside Topshop. We exchanged pleasantries and hugged. But when I found myself in the changing room a few minutes later, I burst into tears for reasons unrelated to the hideously unflattering batwing top that I'd randomly grabbed on the way.

It was time to call my friend Michael. I had just been reading that hiring a "sober best friend" is the must-have accessory for the post-rehab celebrity who wants to stay on the wagon. The pal – not a real friend, in fact, but a well-paid member of one's entourage – accompanies the Hollywood wild child day and night and encourages them to stay clean.

I think that we need the same thing post-break-up: the "sexually sober friend" who stops us from toxic behaviour, such as drunk-dialling an ex or – worse still – having sex with him.

Michael understood that the last thing I needed after seeing my ex was to spend time with loved-up couples. So instead of inviting me to dinner parties, he motivated me to hit the gym every day, he chaperoned me to parties, and encouraged me to stay positive.

"It's been months, and I can't forget him," I told Michael over drinks. He was brutal, but effective. "You did everything you could to make the relationship work, and he gave up on you and walked out. Don't you think you deserve better?"

I knew he was right. I had to stop hanging on to the idea that Paul and I may re-ignite our relationship. After all, he'd made it clear more than once that he saw no future for us. So I went home and pulled out the last souvenir of our romance from my handbag – a plastic hotel key card from our holiday to Thailand. Though I must admit, in my haste to melt ceremoniously the key, I almost ignited my flatmate's cat's tail.

Mentally cleansed, I started getting ready for my date with Ross. We went to the Seduced exhibition at the Barbican, and though loads of men would have been a bit embarrassed about having a first date in the presence of giant penises, we had a few cheeky laughs and learnt a lot about each other.

"I love sushi, but this is taking it a bit too far," he deadpanned when we saw the Katsushika Hokusai image of a woman getting to grips with an octopus. I started to get incredibly horny when I saw the erotic photography, though some of the Mapplethorpes looked painful – even to me. We killed two bottles of red wine at dinner afterwards, and after the restaurant closed, I went home with him.

It felt very natural – we have amazing chemistry. After getting naked, we spent ages just stroking each others' bodies, and after the exhibition and loads of foreplay the sex was exhilarating. While my toes were curling afterwards, he blurted out, "I have to tell you, Catherine, I really, really like you."

"Me too," I said, and meant it. But unfortunately, it doesn't change the fact that I'm still in love with my ex.