I’m in a serious relationship with a man who has two children from previous marriages. Neither of them lives with us, though the older one, a teenager, spends two days a week with us, and the younger one three days a week. I love them, but feel my boyfriend is choosing them over me. He and I both have stressful jobs, yet all his energy is for them. I know I shouldn’t be jealous, but all I seem to get is the bad stuff. He said: “I am responsible for my kids. I love you, but I’m not responsible for your happiness.” I know that’s true, and I do everything to make our time with the children as smooth as possible, but still I feel left out. It’s especially difficult with a stroppy teenager, and I resent my boyfriend disrupting everything for him. I know I’m the adult, but nobody tells you how to cope with being a step-parent.

I admire your honesty. Anybody taking on somebody else’s children finds it a struggle. Sometimes it’s hard enough to summon the selflessness to deal with our own children, let alone somebody else’s. Believe me, I know, having recently taken on a couple of teenagers. Divine as they are, there are inevitable difficulties as we (the kids, too) find ourselves caught up in crosscurrents of new, sometimes conflicting relationships.

It takes time to get used to each other and the advice to the new stepparent is always, “Be yourself.” My advice is different. I think we have to be better than ourselves, and by that I don’t mean playing Pollyanna. It’s fine to admit to negative feelings. In fact, it’s essential. We can deal with them only by bringing them out into the open. Otherwise, “What we resist will persist” as Jung famously put it.

Insecurity and jealousy may not be welcome, but they are a reality. So, how do we deal with them? Well, not by dumping them on the people we love. Instead, we should see them for what they are, as essentially infantile responses. And, yes, we all have them. It is difficult to see our lovers transform into parents. They become suddenly unfamiliar, and unfamiliarity breeds insecurity. We may also find ourselves caught up in jealousy because of a sudden switch of attention and affection, when we are used to having it all to ourselves.

The parent-child relationship excludes everybody except those at its centre. That is its nature. It is particularly exclusive if the kids have been through a difficult divorce and are insecure in their attachment. It will give them a tendency to be emotionally and physically clingy. The thing to understand is that it has nothing to do with you.

So that’s the first (and only) rule of stepparenting – don’t take it personally. The time and energy your boyfriend lavishes on his kids is not a reflection of his lack of love for you. It is a reflection of his love for his kids. As he doesn’t see them as often as he (or they) would like, he may feel guilty for abandoning them. It doesn’t matter that he didn’t actually abandon them: that’s the emotion that he and they may feel about his absence. Guilt drives us to overcompensate, so he may be especially protective and attentive. Again, that has nothing to do with you.

It’s difficult to see that clearly when you’re feeling abandoned and neglected yourself, so you start competing with the kids for affection and attention. Now he has three children to deal with instead of two. That’s why you got the speech about responsibility. He is asking you to be an adult.

Kids go to their parents to get their feelings soothed; adults soothe their own. So he’s right, in one way: he’s not responsible for your happiness. That does not mean he does not contribute to it, or, more important, affect your unhappiness.

You need to explain that, and how you feel. Admit that your impulses are childish, but also that you would like to resolve them in an adult way. That means stating them calmly, without blame or manipulation, and asking his help in finding a solution, together. You could start by setting aside time for the two of you, when the kids aren’t around.

It could be that you have to organise it if he is busy with work and children. I know you’re busy, too, but don’t resent his lack of involvement. Organising kids takes a lot of time. See it as a mutual division of responsibilities and part of the love you feel for him.

He obviously needs support, but I suspect it’s more emotional than practical. Perhaps you might consider leaving the looking-after of his kids to him – and make him your particular priority. Instead of worrying about making time smooth for them, make it smooth for him. When he’s stressed, make him a cup of tea or give him a hug. The kids don’t need another mother. They just need a benign, loving adult. And so does your boyfriend.

If you have a relationship question for Sally, 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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