Sex File: I’m suspicious of his new tricks in the bedroom

My partner has recently acquired some spectacular new moves. We’re both in our 40s and have been together for 15 years. 

I’m delighted, but this sudden change makes me worry that he has been having an affair. Could I be right?

Don’t jump to conclusions — he may be a late developer who has only just discovered that there is more to sex than the missionary position.

Unfortunately, most middle-aged adults never received any formal sex education, so their technique tends to be a process of trial and error, and younger men are more likely to have learnt what they know from watching porn.

A survey of more than 1,000 people carried out last year by Deltapoll for a BBC Three documentary found that porn was the main source of sex education for 55% of men and 34% of women.

More than half agreed that porn had played at least some role in helping them to understand and explore their own sexuality, and 71 per cent felt that porn has given them ideas for things to try sexually.

I am a fan of OMGYes, a sex-education website that includes touch-screen simulations to practise techniques on an iPad or a smartphone.

Then there’s the TED Talks playlist “Sex Ed For Adults” (ted.com). Or you could even try suzigodson.com.

We tend to think of sex as a drive, or an instinct, so rarely see it as something that can be learnt.

In fact, lovemaking is a set of skills that can be developed.

The internet has its downsides, but it is brilliant for sex education.

Maybe your partner decided that he wanted a more sophisticated understanding.

Or, of course, your worst fear could in fact be true — he may be having an affair.

Although this is not always the case, sudden changes in sexual behaviour can be an indication of infidelity.

Men who are engaged in serious affairs tend to withdraw from sex with their primary partner, but a casual fling can also increase the level of sexual activity within the primary relationship.

The novelty of sex with someone new lights the fire, and their appetite for sex increases.

Guilt can also make cheaters more attentive, so, bizarrely, an unfaithful partner can sometimes become a lot nicer.

Gifts and flowers may suddenly become a feature of the relationship.

That said, if your partner was cheating, your gut instinct would be screaming and you would feel emotionally distant from him. 

You would also notice other signs — he would be less reliable and his behaviour would change in other ways; he would be guarded about his mobile phone, having turned off any location sharing and changed his passwords.

Since you don’t mention other changes, your partner may have simply learnt a few new tricks somewhere and found that you responded enthusiastically to them.

Complimenting a partner’s sexual generosity is not something we always remember to do, but gratitude can be a powerful motivator.

I suspect that your appreciation has created a positive-feedback loop.

Emboldened by your favourable response, your newly confident partner may have felt encouraged to explore ever more adventurous sexual techniques.

You could ask him what has motivated the change, but choose your moment.

You are more likely to find out his inner secrets during a postcoital cuddle than a kitchen interrogation.

Pillow talk increases intimacy, and research has shown that couples who are affectionate after sex have higher levels of sexual and relational satisfaction.

Great sex and a better relationship after 15 years together? Sounds good to me.

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