I’ve been with my boyfriend for 10 months and I’ve never been happier. We’ve got loads in common and he’s driven, funny and kind; he’s my absolute best friend – not to mention the fact he is gorgeous. The problem, however, is that I don’t feel very sexually driven any more. Before him, I had never had a real relationship, just “situationships” where I was being treated pretty badly by men but I was horny and excited to have sex with them. I don’t feel that with my boyfriend, though. We do still have sex but it’s not on a regular basis because I’d rather just relax with him, or be kissing, cuddling, talking or sleeping. I just can’t really be bothered with sex. When we do have intercourse, while it is enjoyable, I always want it over quite quickly. I really can’t see myself being very sexual with anyone once I’m in a relationship with them. I truly believe he is my soulmate and I don’t want this to be something that can ruin the relationship. It doesn’t seem to bother him too much (yet) – I think he mostly cares about spending quality time with me. But I can’t help but think there’s something wrong with me – or us. Is there anything I can do? Heightened eroticism often occurs in unsustainable situations, usually where there is something wrong, taboo or forbidden. Attraction to an unsanctioned partner or to someone in an inappropriate environment can really increase the erotic charge. But, while some forbidden liaisons last, most are fleeting or lose some of the spark if they become sanctioned. In the past you found casual sex inspiring, but in a lasting relationship you will have to discover how to have satisfying sex without the thrill of a one-night stand. If there is genuine attraction between you and your current partner, this should be possible. If, however, your current situation is a relationship based more on a fantasy of what you think you want, it may not develop. Meanwhile, it would be worth investigating your lowered sexual interest as a symptom of some other cause, such as depression, anxiety, stress, or medication side-effects. Pamela Stephenson Connolly is a US-based psychotherapist who specialises in treating sexual disorders. If you would like advice from Pamela on sexual matters, send us a brief description of your concerns to private.lives@theguardian.com (please don’t send attachments). Each week, Pamela chooses one problem to answer, which will be published online. She regrets that she cannot enter into personal correspondence. Submissions are subject to our terms and conditions. Comments on this piece are premoderated to ensure discussion remains on topics raised by the writer. Please be aware there may be a short delay in comments appearing on the site.