Over the last few years, lesbianism has become fashionable. Think Lindsay Lohan and Sam Ronson - and Katy Perry's 2008 hit I Kissed a Girl. You might think that this would make being gay easier, but for me it hasn't really been like that.

My age was in single figures when I realised I was different. At school I had crushes on girls, though I didn't talk about them or act on them: I knew not to. My friends were beginning to show an interest in boys, swooning over pictures of Boyzone in teen mags. I was more interested in the Spice Girls (particularly Baby Spice), and the model in a certain Levi's ad who aroused feelings that, even then, I could identify as definitely sexual.

I was 10 when I first decided to come out to my mother – even then, I had been wanting to tell someone for a long time. I had just discovered the word "lesbian" (cheers Ben Chambers, year 6, for introducing it to me), so that was the word I used. No one else was around when I went into my mum's room, got into bed with her, and reached out for a hug. I was really crying, but she wasn't disgusted. She explained that these sorts of feelings were normal for a child reaching puberty, and that as I got older I would "work things out". She told me how much she loved me and made it clear she and my dad would have no problem if I turned out to be gay.

In some ways, it was the best response I could have hoped for – understanding and non-judgmental. But as well as feeling relieved, I felt oddly stifled. I had hoped for immediate acceptance of who I was, but was left instead with the thought that perhaps if I waited long enough, things would change. I don't recall whether I told my mum that I was certain of my sexuality, though I know that was how I felt. I don't blame her. She gave me the best advice she could. But I couldn't help wondering how I would "sort myself out". Would I suddenly become more gay, or less gay?

The net effect was that I pretty much forgot about it. I just went back to being an average 10-year-old and clung to the fact that my mum had said I might be going through a phase. That possibility slowly formed the basis of a massive denial. In my teens I tried to fit in with my straight friends and convince myself that I fancied boys. I even had a couple of short relationships. At 16 I told my friends that I was bi, and couldn't have been more surprised when a lot of them came out as bi too. Many had relationships with other girls long before I did.

At this stage, my relationships – if you could call them that – were all with boys. Then came the anger: why weren't they working? Why was the sex leaving me feeling revolted? But still I held on to the conviction that eventually I would find a nice boy, and we'd get married, have children. I spent my first two years at university preoccupied by these thoughts. To the extent that you can believe something when you're in denial, I believed I was bisexual, and the men I had relationships with – mainly one-night stands – accepted me as such until, finally, I came out to my friends last year.

Initially, they didn't take me seriously at all, thinking instead that I had had enough of men. But after a lot of insistence they took me at my word. After that, I told my mum again. This time we were having a cup of tea and I don't think there were tears though, strangely, I don't recall this coming out as vividly as the one when I was 10. Now, I was coming to her as an adult, and she knew it was no longer a phase.

Although I feel tremendous relief, at 21 I'm also entering a new and isolated world. I feel this most when I'm at a party, single, drunk and surrounded by attractive women. Here we go, right? Actually, no. At least not without making a gigantic assumption about some of the women in the room. This is my new world – the world of the young, single, newly out woman. It's deeply confusing – not to mention lonely, though in the last year I have finally had my first short relationship with a woman.

Coming out as a lesbian is not, as many straight people seem to think, akin to entering an exclusive, trendy club, where inhibitions are chucked aside along with bras. Is it possible that we've become too liberal to admit that being gay is still hard? The other day my mum came out on my behalf to one of her girlfriends, who said: "Wow, you got one! Congratulations." But for me, being accepted by the straight world doesn't equal happiness.

As a lesbian, meeting a partner can be fraught. Finding a compatible woman is one thing; discerning whether or not she's gay is another. Unless, of course, you turn to the gay scene. But I don't want to define myself by my sexuality. I think my penchants for Curb Your Enthusiasm, Mexican folk art and camembert are more significant markers of my personality than whom I choose to go to bed with.

So, yes, it makes me sad that it is so hard to meet gay women other than via The Scene. Like any group or culture formed as a result of persecution, the gay scene is isolated, and often bitter. Gay and straight can be a real us-and-them situation. This is so frustrating if all you want to be is yourself.

What complicates matters even more is that I fancy women who look like women. I have nothing against tomboyish, or even outright masculine lesbians. They're being who they want to be. But I don't want to date them. The downer is that as far as I can tell with my fledgling gaydar, these women make up a considerable proportion of the gay scene, which leaves me as a minority within an already very small minority: a feminine lesbian seeking one of her own kind. It's like being a death metal fan who is also passionate about beekeeping.

My confused prepubescent days are behind me, but I find myself in mourning – grieving for the heterosexuality that might have been. I would never have chosen to be a lesbian. I hope that feeling changes.