My wife of 30 years and I are separated (but still live in the same flat) and own a very successful business together. About nine years ago, we had a massive row and she told me she didn’t love me. I am quite a dominant person, but my mother had dementia and my wife had myalgic encephalomyelitis (ME) for a long time, so it fell to me to hold everything together. We went to five or six counsellors, separated in our marriage but still kept trying to make it work. All this time, we have been a dynamic team running our business. Then, about a year ago, she didn’t want anything more to do with me sexually, wouldn’t kiss me and refused to have sex. We can’t seem to move on. I am 66, she is 63 and I feel time is not on our side.

You are obviously a person who has been successful in business and, it seems, it is extremely important to you to succeed in all things, including your relationship. But the kind of problem-solving you need to apply in your work is inadequate in matters of love and sex. It is never easy to combine work and eroticism within a marriage, and, on top of that, you have suffered painful losses.

After many years of trying your best, I can understand why it is so hard for you to let go, but this relationship – apart from the business connection – has probably run its course. Since neither of you is happy, could you try to let go of the need to “succeed” in saving this relationship? Could you reframe the idea of failure in your marriage as an opportunity? A chance for you to have many more good and happier years – but apart, and perhaps with other people? You both deserve happiness, healing and a good sex life, but, while you are still living together, this will not be possible.

• Pamela Stephenson Connolly is a US-based psychotherapist who specialises in treating sexual disorders.

• If you would like advice from Pamela Stephenson Connolly on sexual matters, send us a brief description of your concerns to private.lives@theguardian.com (please don’t send attachments). Submissions are subject to our terms and conditions: see gu.com/letters-terms.