I am a fortysomething man in a long-term relationship – nearly 20 years – and have two children. For the past 10 years my partner has been having short-term lovers. These were clandestine, but more recently she has stopped hiding, called our relationship “open”, and currently has a lover who I do know about. But this “open relationship” can only be one-sided, because she is jealous and suspicious while I am basically not polyamorous. So why stay together? We get on, communicate well (other than the no-go zone of her other love life), rarely argue, are bonded by bringing up our children and are financially tied together.

However, the years of suppressing my emotions – of jealousy, rejection, insecurity, being lied to – have left me broken. Sex (which we still occasionally do have) has become stressed: if I don’t perform enthusiastically, it will justify her seeking other lovers. Also, I am expected to remain sexually attracted to her, which gets more difficult when I know she’s been with someone else recently. We had frank talks when she offered to end her extramarital affairs and be monogamous with me – or plan how we might separate without affecting our children. We were both very upset, as we are very much still in love, and wish the sex side of our relationship wasn’t such a terrible mess.

But it has occurred to me that I am emotionally and sexually broken after this past decade. If I was single again – or my partner was to become monogamous with me again – I don’t think I would be a viable person to be in a relationship with. How do I start to repair myself, inside or outside this relationship?

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It’s high time you set boundaries with your partner. In the past, you have been enormously accommodating – more than you really wanted to be – and that has left you with residual resentment. Underlying resentment is one of the most common causes of lowered libido, so no wonder you struggle to “perform enthusiastically”. It is highly likely that, if you stand your ground about the things that upset you – everything that gives you a sense that the unspoken contract between you is an unfair one – and ask specifically for the changes you need, you will elicit better behaviour and more appreciation, respect and even sexual interest from her. You will also feel far better about yourself. A restoration of the power balance between you should have the further effect of increasing the erotic connection between you. Then you will be in a better position to decide what you truly want and make the larger decisions.

• 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 [email protected] (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: see gu.com/letters-terms.

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