I’m a gay man who is in a long-term relationship. When we started dating I was originally a top, but I haven’t enjoyed it for a long time and am unable to perform. I’ve realised over time that I am now a “side” and only enjoy oral sex. I have not told my partner this; he is still a bottom and there is a lot of frustration about our sex life. I’m unsure what to do. You are allowed to change your mind. It would be best to be frank about this with your partner, so have a calm and honest talk with him and help him to understand your feelings about this – then give him an opportunity to express his feelings as well. There is often room for negotiation regarding possible solutions, so try to approach it as a couple’s problem that needs to be solved jointly, rather than a conflict. It is not uncommon for a person to change their preferred sexual style, and you have every right to do so. However, it would be wise to acknowledge his feelings about it, which could be expressed as sadness at losing his own preferred style or even anger. But no matter how important sex is to each of you, together your broader bond and connection is far more significant; you can work through this. 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.