Sex File: We had great no-strings sex, has commitment killed our spark?

It can be anywhere from six months to two years for the honeymoon period to end.

I am a divorcee and for six months had been having exciting, no-strings sex with a man I met on a dating app. Recently, we decided to become a couple, but while I love his company, the sex has gone off the boil. Is this to do with the act of committing and the assumption we're always now available to each other? How do we get back to our no-strings passion?

There was a telling omission in your letter: the absence of any reference to emotion. You say you love this man's "company" but is that it? Most couples who have been together for only six months are still in a state of such profound limerence that they can barely function.

Scientists liken the rush of oxytocin, norepinephrine and dopamine that flood the loved-up human brain to addiction. MRI scans show that when someone who is in love looks at a photo of the person they are besotted with, the same neural pathways that are stimulated by cocaine light up.

It can be anywhere from six months to two years for the honeymoon period to end. That sort of fits with your timeline but the difference is that you made the decision to become monogamous only recently. Before that, I assume one or both of you was involved in, or open to the idea of, sexual relationships with other people.

Although polyamory attracts so much media attention that it seems almost commonplace, most men and women favour monogamy, according to 2023 research by Andrew Thomas at Swansea University.

Since it sounds as though you and your partner are not even cohabiting yet, I very much doubt that the "assumption of availability" is the thing that is creating the issue of your sex life going off the boil. Rather, it is the shock of the transition from non-monogamy to commitment.

If the excitement of your former "no-strings" passion was fuelled by the possibility of other sexual partners, you either need to reconsider your commitment to monogamy or find ways to make sex with each other equally exciting. 

The best way to intensify your sexual connection is to deepen your emotional one.

Being honest about your motivations would be a good start. The decision to be exclusive must have been driven by the desire for commitment but it may also have been driven by a desire to remove each other from the market so that neither of you had to compete with rival sexual partners. That tension would make the transition to monogamy more demanding for anyone, but admitting that you care enough to make that commitment would build trust.

But if your "'no-strings" passion was fuelled by dating multiple partners in the beginning then perhaps the confines of a monogamous relationship might not work for you. People who have been in non-monogamous relationships can successfully transition to monogamy but it requires adjustment and clear lines of communication.

People who have experienced difficult or painful relationships or break-ups may avoid intimacy as a way of protecting themselves. In that context, choosing non-monogamous or more casual relationships that require less emotional investment might seem like a safer avenue but it is equally a way of evading the emotional complexity of commitment.

Figuring out how your past is informing the decisions you are making may help determine the relationship's next steps - and its future.

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