I am a woman in my early 40s and have been married for almost 20 years. Over the past few years we have rarely had sex. This hasn’t really bothered me – I’d decided I had turned asexual. We had problems conceiving, which was a bit of a passion killer, but did eventually have a baby eight years ago (also a bit of a passion killer!). Our relationship isn’t great in other ways, as we are impatient and irritable with each other. I have long wondered if we will not stay together once our son is older, but so far, so ordinary.

A month ago I started having sexual fantasies about a man I say hello to on the school run. I feel like a lovesick teenager in that I can’t stop thinking about him, to the extent that I can’t sleep at night. It is almost like a switch has been turned back on as I haven’t had such thoughts for years and now I feel consumed by them. I recently initiated sex with my husband but it was perfunctory and unsatisfying. I have no intention of pursuing the school dad – who I barely know – as I assume he is just a representation of desire. But I feel guilty that I am thinking about him, as he is married with young children, and also confused that I am having such thoughts at all. Is it normal to suddenly feel desire again – and for an almost stranger – after so long of being not bothered? I don’t know how to stop the thoughts or channel them into something more positive.

The school dad is a troubling blessing. A blessing, because he has become a catalyst for you to reawaken the sexually alive “you”, but troubling, because you like this rediscovered aspect of yourself and know it could to be hard to relinquish it. In loving relationships, who you perceive yourself to be in the context of your partner is extremely important. In the context of your fantasy lover, you are desirous and desirable, while in the current context of your relationship with your husband you see yourself as sexually dull, a mother focused on her child. Couples who have issues conceiving or who go through IVF often experience an aftermath of sexual malaise, because sex has become a chore linked with anxiety. And having young children challenges a couple’s sexual connection due to fatigue, hormonal changes, opportunity and more. You now have a chance to reignite passion in your marriage, but you will have to work at it. Talk deeply and lovingly together and deal with any underlying pain or resentments. Once the air is cleared, seek quality time alone. Returning to places and styles of courtship usually helps. Try to let him see your seductive side, not just the mother and caring wife – and give him a chance to allow you to see him in the role that attracted you to him in the first place.

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

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