How much weight do you place on sex frequency and your happiness?

I’m 32 years old and my sex life with my girlfriend is brilliant, but friends in much longer-term relationships have warned me it will deplete over time, and become less exciting. Is it possible to stop this decline happening?

Habit is, as you recognise, a problematic aspect of any long-term sexual relationship, but long-term companionship offers such enormous physical, emotional and social benefits that most people figure the trade off is worth it.

However, as long as a relationship remains meaningful, familiarity does not translate into boredom. When you are single you are able to have lots of relationships with different people.

When you are part of a couple you have lots of different relationships with one person. You fall in and out of love with each other all the time. You have novel sex. You have dull sex. You have make-up sex.

Sexual relationships are not static and boredom is not a passive response to over- familiarity.

It is something one or both partners actively allows to happen to a sexual relationship that is almost certainly under- performing on multiple levels.

Several surveys have shown relationship duration is positively correlated with a decline in sexual desire, sexual satisfaction, and sexual frequency, however it is not necessarily a linear, or even an inevitable, progression.

Sexual frequency can increase, or, in response to an array of mental, physical, relational, social, even financial changes.

Think about it. When you get ill, chances are you don’t feel like having sex. And if, for example, you and your girlfriend ever decide to have a baby, chances are, your sexual frequency will go through the roof.

Since none of us can predict the future, there is not much point in worrying about occasional fluctuations in sexual activity, unless of course, they correlate with a worrying decline in relationship satisfaction.

Sexual and relational satisfaction are intrinsically linked, which is why sexual difficulties are such a useful gauge of the health of a relationship. Stable relationships, in which both partners consider themselves happy and satisfied, are more likely to report higher rates of sexual activity than relationships characterised by friction and strain.

It makes intuitive sense that couples who like each other are more likely to touch each other, and because this association is bi-directional, the recipe for a good sex life is pretty much the same as the recipe for having a good relationship.