I have been married for 31 years. I love my husband and I know he is crazy about me, but we have a problem: we’re not having sex and I don’t understand why.

We used to have the best and most fabulous sex life – creative, passionate – but now we haven’t had sex at all for nearly three years (we’re both in our 50s). I really miss it and I have spoken to him about it. He misses sex, too, but he doesn’t know what’s happening to him (he’s had blood tests and everything is OK).

I told him just recently that I love him and don’t want anyone else, but I can’t wait for him any more; I need to have sex and am ready to pay for a sexual encounter. I would love our sex life back, but I don’t think it’s fair to wait for him to make a decision about it. He thinks I shouldn’t have sex with anyone other than him, but the problem is he is not providing this for me, and I am fed up with having to pleasure myself.

First, it is important for you to know why your husband is now seemingly uninterested in sex. It could be that he is suffering from a sexual disorder – a blood test would not reveal all possibilities. Some physical diseases or conditions can be root causes of low libido, as can psychological problems. Perhaps he is taking medication that affects some part of his sexual response cycle. You both deserve to understand the reasons, but pressuring him for sex will only make matters worse. Gently let him know that you would like to help him find answers through consultation with a sexuality specialist. Be his understanding advocate in seeking answers.

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.