My issue is that in long-term relationships I lose all interest in sex. I’m great when I first meet someone: very interested, initiate sex, easily turned on and adventurous. Once settled into a relationship, my libido goes and sex starts to feel like a chore. My boyfriend is very understanding and patient, but I feel guilty.

Sustaining sexual passion is never easy, so you are far from unique in having such a struggle. All kinds of challenges typically arise, and it is worth putting in some time and energy to figure out the reasons. At the beginning of a relationship, sex is often so spontaneous and new that it is easy to make room for it. But after a certain amount of time together, many couples stop prioritising their love-making time, allowing other interests to get in the way. If this is the case for you, change this and start planning quality time together with no interruptions.

Very often, a long-term couple reaches a plateau. Things can be improved by communicating desires and fantasies that could lead to new erotic styles and increase the sexual spark. Problems such as fatigue, overwork, stress, family problems, being exhausted by young children, losing pride in your body and harboring unexpressed anger towards a partner can all contribute to sexual disinterest and need to be addressed. Instead of accepting the untruth that this is your own recurring problem, as a couple discover and work on whatever specific issues are contributing to this problem, emphasise the preciousness of your erotic connection and vow to keep it alive.

• Pamela Stephenson Connolly is a 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