Sex File: I still fantasise about my ex — how do I finally move on?

Sex file: Now I'm dating again, my ex keeps popping into my head in bed. How do I finally move on?

Our divorce was pretty miserable, following several years of little to no sex at all. But now I'm dating again, my ex keeps popping into my head in bed. We're cordial for the kids' sake but I have no desire to get back together. How do I finally move on?

Sexual fantasies about former partners are a confusing, but extremely common, phenomenon. When they invade your thoughts during sex with someone else, it is difficult not to interpret them as an indication that sex might have been better with your ex — but it is not a fair comparison. You can't judge a person you have known for a week against a marriage that lasted maybe 10 years or more.

You are, at least, very clear that you have no desire to get back together with your ex. But thinking about him during sex prevents you from being present with a new partner. And trying to suppress fantasies that feel inappropriate only steals your focus, making it difficult to enjoy sex.

One of the main reasons divorcees sabotage the possibility of a new sexual relationship is that they are still smarting from the pain of the end of their marriage. Dating after a divorce is a big step and it stirs up all sorts of emotions. Women, in particular, often intend to keep things casual at first, especially if they have children, because they want to avoid becoming emotionally involved too quickly.

Humans don't really work like that, though, and by the time a woman finds someone she likes enough to have sex with, she is already invested in the possibility of a new relationship. While that feels exciting, it also creates jeopardy. After giving a huge amount of time and effort to their marriage, the thought of putting all that into another relationship that has no guarantee of success is scary.

Fear is not a sexy emotion. It makes people hypervigilant and instead of enjoying the moment, they find themselves overthinking it and searching for red flags.

It is also true that no matter how bad the divorce was, when there are no daily reminders of the stressors that led to a relationship's demise, it can be easier to romanticise the good bits of it than to contemplate the mountain of 'what ifs' surrounding a potential new one. It can feel safer to think about the ex you once loved than the stranger you are still getting to know and who they might turn out to be. This tension is what causes otherwise intelligent people to idealise truly terrible relationships. Recognising this tendency and challenging it in a rational way will help you to untangle your attachment to an unhelpful ideal.

Another thought that commonly holds back the newly divorced is that if they are having sex with a new partner, the chances are their ex is doing the same thing. Even though they know the marriage needed to end, the thought of their ex getting it on with someone else can rouse the green-eyed monster. Rationality goes out of the window and they find themselves obsessing about what they are doing and who they are with.

If this rings a bell, find a pen and paper and write down all the reasons your marriage ended. Remind yourself of the misery, the celibacy, and the emotional cost. Change won't happen overnight, so you need to give yourself time. Moving on after divorce can take years and your ultimate goal is not to forgive and forget, but to reach a state of complete indifference. When you get to the point where you genuinely don't give a damn about your ex, you will feel free.

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