People wonder why asexuals bother to get together, but Amanda and I have been happily married for nine months now and we're both still virgins. Some people even think asexuality doesn't exist. It's so underrepresented, I can understand why people are skeptical. I was too, even though I was perfectly used to thinking of myself in this way. For years I just thought I was the only person in the world who felt like this.

My parents are agricultural scientists, so I've lived overseas since around the age of 10. I was in India until I was 16, then Zimbabwe for two years, and then Kuwait. I studied in China and New York, before settling in London. Even at 10, I had a sense that I didn't want to get married and have children. I know a lot of kids say things like that, but I didn't change my mind about it later on. I wasn't interested in relationships or finding a girlfriend, and was very sure I didn't have an interest in boys either.

Gradually my school friends spent more and more time talking about girls and pursuing relationships, but I could never grasp what they were expecting to get out of it. There were family parties in India where all the kids would gather outside in the garden.

I was 13 and had a best friend, Kasim, who was a year younger than me. He had a crush on an Australian girl called Jessica - everyone seemed to think she was the prettiest. We had lots of whispered discussions about what he could say to her, and even though I thought it was a ridiculous game, I wanted to fit in, so I pretended I had a crush too - on a French girl called Sylvie. She was a safe bet because she was so unlikely to reciprocate. I knew she wasn't at all interested in me. I'd just discuss her with the boys.

There were times as I got older when girls did seem interested in me, but I always deliberately ignored their signals. I wanted to avoid getting into a situation I'd feel uncomfortable with, so I never even kissed a girl. The first girl I kissed became my wife.

When I was 13, my father gave me a book on sex education. I felt as if I was reading about a foreign culture; I just couldn't see why anyone would go to so much trouble just to have sex. I tried looking at pornography on the internet. I wasn't disgusted or appalled - it was just boring, like looking at wallpaper.

Masturbation was another topic of conversation in those days, and I did masturbate. It wasn't a sexual urge for me, I didn't fantasise, it was just something my body decided to do. People say about asexuals: "But if they masturbate doesn't that make them sexual?" It's hard to explain, but if you're asexual you don't necessarily feel an explicit connection between masturbation and sexual orientation. It's just part of having a human body - a physical, biological process.

After we moved to Zimbabwe I went back to visit my old friend Kasim. The last time we'd seen each other we'd been into computer games, drinking Coke and going for pizza. Two years on, it was a shock to see how much Kasim had changed. Sex was his major preoccupation. He had a girlfriend and was on the brink of going all the way with her. One afternoon we were with some of Kasim's friends, and he began goading two of the girls into kissing each other in front of a camera. The whole atmosphere was really charged, and I felt out of my depth. I'd fallen behind. Kasim had been my friend a long time, but he'd entered this different world without me.

By the time I went to university, I was happy to let people wonder about my sexuality. I wasn't pretending to talk about girls any more. Some people assumed I was gay, but my best friend Simon was the first person to confront me directly. We were studying in Hangzhou, in China, just south of Shanghai. It's a very beautiful city, on a lake with mountains, and we were walking through the streets when Simon asked me outright. First he made a joke about whether "I liked girls ... or boys?" I laughed but he persisted and said "So what are you?" I just said, "I'm not straight and I'm not gay, and that's it, full stop." Back then I didn't know what term to use.

The following summer I was surfing the internet when I read a post from a girl who wasn't attracted to anyone. Someone had suggested she should be aware of "asexuality", and gave the address of a website: asexuality.org. When I went to the site and read the material, I was quite dismissive at first, because you just don't hear about other asexuals. Since Freud and Kinsey, and even to an extent the sexual revolution of the 60s, we tend to believe anyone without a sexual orientation must be repressed or delusional. Asexuality is therefore an impossibility. Kinsey labelled us "X", a statistical throwaway category for anyone damaged to the point where they can't express any sexuality.

Gradually, though, through visiting the site, I came to realise that these were just ordinary people; people who were writing things I'd thought myself, but had never heard anyone else express. It was such a relief. Finally I had a label - a way to explain myself that could settle all the awkwardness and questioning.

I told my close friends straightaway. Only one female friend didn't really believe me. I think she thought I was secretly in love with her.

Back at college I decided to get it over with in one day by wearing a T-shirt saying: "Asexuality is not just for amoebas". I was nervous, but I'd already told a dozen or so people, and was used to answering the same questions over and over. No one has ever reacted really badly to me - I've been lucky.

I told my mother shortly after finding the asexual website, and she said: "Well as long as you understand the possibility that one of these days you'll meet someone and want to settle down with them." I wasn't so sure. I'd already resigned myself to a solitary existence. I'd convinced myself I could form strong friendships and was independent enough to fare OK. Luckily my mother always ends up being right about everything.

When my studies took me to New York, I got more involved with the asexual community there. I posted messages on their website and there were regular meet-ups in a little pink tea shop in the East Village - I guess you could call it the asexual equivalent of a gay bar.

One day I got an email from Amanda. She was asexual, living close by, and offered to show me around the neighbourhood. In case she was cruising for an asexual boyfriend, I responded with a warning that I was "vehemently anti-romantic". But we met up anyway, for tea and ice-skating, and we took to meeting a lot.

I loved Amanda's attitude to life and enjoyed hanging out with her. And she was pretty. At first I tried to treat it like any other friendship. Then I found myself travelling four miles downtown to deliver sandwiches when she told me she was hungry. Two months in, we were at a gig and it seemed like a good idea to hold her hand. I felt cautious about it but just wanted to. I wondered if I could. Then I found I couldn't let go.

That evening ended with us agreeing that our friendship was an important thing. We wanted to commit for life. In the asexual community we don't form relationships lightly. If you don't want to spend the rest of your life with a person, there's no reason to make such a special commitment.

When we announced our engagement, our families were happy for us, and our friends in the asexual community were particularly pleased. On our wedding night, my mother-in-law insisted on booking us into a honeymoon suite, so we invited all our friends to an after party. We played Scrabble late into the night and everyone stayed over and slept on the hotel-room floor.

People always ask how our marriage is different from just being friends, but I think a lot of relationships are about that - being friends. We have built on our friendship, rather than scrapping it and moving on somewhere else. The obvious way we differ is that we don't have sex, though we do kiss and cuddle. We like to joke that the longer we're married the less unusual this is. By the time we've been married five years we'll be just like everyone else.

Do I feel as if I'm missing out on something? Not really. We've decided that if either of us wants to try sex out in the future then we will see what we can do. We would both be willing to compromise because we're in a relationship and that's what you do.

When it comes to the future and to children, we're big advocates of adoption. We're not so fussed about passing on our own genes. Right now we're quite happy with what we've got. After moving around so much, I can say now that wherever Amanda is - that's home.

· Paul Cox was interviewed by Bridget O'Donnell. Some names have been changed.

· Do you have a story to tell about your life? Email it to my.story@theguardian.com. If possible, include a phone number.