I left my wife and children for another woman and we got married 18 months ago. But since then, we have had a lot of family issues – we have five kids from previous relationships, all between the ages of five and 11. I left her a month ago in the hope of being with my children, and I’ve been hanging around with them and my ex-wife. But I miss my current wife. I truly love her with all my heart, no question – we have the best adult relationship when we are alone. I don’t know what to do: do I stay with my children and the woman I don’t love as much, or go back to the woman I completely love, but with the kid issues? My children now hope that their mum and I will get together again, and they will be devastated if I don’t come back. I don’t want to hurt them again. Believe me, I would do anything for my kids – I would die for them. But when they are grown up, I want to be with my current wife. I have dug a hole, and no matter which way I go, someone will get hurt.

I don’t usually feel cross with people, but right now I do. Selfishness, when it comes to children, makes me very cross indeed. Children have no power. They are forced to endure the choices that adults make. The only power they have is in making their feelings plain, so perhaps it is not surprising that your stepchildren are playing up.

They did not choose you to be their stepfather. You chose that role. With choice comes responsibility. It was up to you to choose whether to fight with them or to act like an adult and show patience and understanding in the face of their distress. Instead, you chose to leave.

Worse, you went back to the children whose lives you had already disrupted, confusing and hurting them even more. And you say you would do anything for your kids. I hope you mean that, but your letter is entirely about your own feelings. At no point do you mention how anybody else might feel.

I suspect that you’ve run back to your own children because they give you the unquestioning devotion that young children are biologically programmed to give – no matter how appallingly their parents behave – and it makes you feel important and wanted. It’s just your protestations don’t ring true. “I would die for them,” you say. If that’s the case, I wonder why you put your own feelings first when you left.

Obviously, your stepchildren don’t offer you unconditional love. You’re not their father, but a man who doesn’t want them. I dread to think how they are feeling now. It’s one thing for kids to kick up a fuss, it’s quite another to be left feeling responsible and guilty. Then there’s the emotional and financial mess you’ve no doubt left their mother in, and which they will have to help mop up.

As to the feelings of the women involved, words fail me. If your ex-wife is prepared to take you back, then for the sake of your children and stepchildren, you might consider staying. Perhaps your stepchildren are better off without you. Even if you haven’t told them you would prefer it if they weren’t around, kids have a sixth sense. They will know instinctively that the only thing you care about is the “adult relationship” you have when you’re alone with their mother. Well, guess what? There is nothing “adult” about a relationship based on fantasy. The reality is that your new wife has three kids and you knew that, not only when you got together, but also when you promised, “for better, for worse”.

As to your own kids, if you do stay, you have to learn to put them first, and their mother, too, whom you “don’t love as much”. Poor woman; I just hope she doesn’t know. It’s up to you not only to make sure that she doesn’t, but to make her feel wanted and safe. How that can happen, after your past behaviour, I cannot imagine.

As to how your present wife is feeling, I cannot bear to think, but as you are not prepared to engage with her kids, she doesn’t really have the option of a future with you.

What is needed now is clarity. Decide what you are going to do and stick to it. If you go back and forth, the children will learn that nobody and nothing is to be trusted. They will never feel emotionally safe, and if they don’t feel safe as children, how can they learn who to trust and how to have good relationships? Your erratic behaviour is setting them up for potential future misery.

All you can do now is try to undo the damage you have done. How you personally feel about anything, including your new wife, is irrelevant. Just don’t keep her dangling, or allow her to fantasise about what you two will be doing in 10 years’ time. It is unbearably cruel to make somebody live in the future and waste their life in anticipation. Be clear and be kind. Don’t make false promises. You have messed up the lives of seven people. The least you can do is tell the truth.

If you have a relationship question for Sally Brampton, e-mail sally.brampton@sunday-times.co.uk. In case of publication, names will be withheld. We’re sorry, but Sally cannot answer letters personally

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