Sex File: Why are things so hot in bed since I  found out he was sexting another woman? 

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I discovered some inappropriate texts to another woman on my husband's phone two months ago. We slept in separate beds while I considered whether I wanted to continue our marriage. He has done a lot of work to prove he is sorry, and the new openness between us seems to have made sex even better. Is this normal or healthy so soon after something like this?

Much as I am sure you would like to believe that your husband was only in it for the validation, you don't get from zero to inappropriate without mutual chemistry. Extramarital sex has an unfair advantage because it's hard for familiarity to compete with novelty. The magnetic pull of a secret new attraction can make the smartest people lose their head.

He is now doing lots of work to minimise the affair and make it up to you. That's utterly predictable. There is nothing like getting caught cheating to make someone realise how much they have to lose if they blow their marriage up. The devastating reality of losing their partner, their family, their home, their pension and their centre of gravity can strip away years of complacency and temporarily shock a marriage back to life.

It is a bidirectional phenomenon. The person who has cheated becomes obsessed with proving their commitment, seeking forgiveness and winning back their partner. The person who has been betrayed feels such emotional turmoil that it triggers an intense craving for the comfort and familiarity of the relationship they had before the affair turned their world upside down.

In your longer letter, you worry that you are having great sex with him to prove that you are the better choice, but sex is actually a way for both of you to cling on, to reclaim the relationship, to avoid facing the future. In a fear-fuelled crisis, intimacy feels incredibly similar to the sex you had when you first fell in love. You are driven by adrenaline in the pursuit of dopamine, but like all drug-induced states, eventually the passion burns out, reality bites, and the marriage finds itself back where it was before the bomb dropped.

It has only been two months, so I don't really think you should be making any decisions just yet. People make mistakes, and lots of marriages survive infidelity, but real repair only happens if you are both willing to confront the weaknesses in your marriage. Basically, if you don't neutralise this bomb, it will detonate every time you have an argument for decades to come.

It is never easy, and professional help is almost always required, but before any of this can even begin to happen, there needs to be truth. Infidelity is comparable to an addiction, and it can't be turned off like a tap.

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