I need some wise words. For four months, I’ve been having a relationship with a man who lives with his girlfriend and young children. He came clean on our first date. I was so disappointed, as I already felt there was something special between us. He says he’s not happy and that having someone would motivate him to make the difficult move of breaking away. My heart wanted to keep seeing him so badly, but my head told me to leave. My head lost, and now we are in love. I know I’m being selfish engaging in a relationship that may hurt others, as well as, quite possibly, myself. We both realise it’s early days, so there have been no promises – only indications that this is what he is working towards. We know life would not be easy, as I imagine his ex and children will feel bitter. Also, my mother won’t approve as he has a different-coloured skin, and she says a mixed-race relationship would break her heart. He says things I believe are genuine, but I sometimes doubt it will work out and wonder if I’m being stupid, even though I know our love is real.

First, you need to admit that you made a choice, and that with choices come consequences and responsibilities. Are you really facing up to them? You call it a “relationship” rather than using the more brutal word “affair”, which makes me wonder if you’re acknowledging reality.

You say you “may” hurt others and that you “imagine” they will feel bitter. Be honest. Unless his relationship with his girlfriend has completely disintegrated (in which case, any discussions about separation would be mutual), you will cause intense pain. There is no “may” about it. Sometimes pain can’t be helped, but the inflicting of it can be done gently or with great cruelty. Emotional dishonesty is at the heart of most cruelty, so I wonder how truthful your lover is being in lining up the next relationship when the present one is not resolved.

Why does he need somebody to motivate him? Is he incapable of knowing his own mind, or is his present unhappiness not as great as he is making out (in other words, he’ll put up with it until somebody else comes along)? These are hard questions you have to ask yourself. There are children involved – young hearts and minds that can be shattered without proper love, care and attention. You will be responsible (albeit partly) for their unhappiness and just as responsible for healing it. Are you prepared for that, or even for the simple daily grind of caring for kids?

Try to lose the romantic blinkers. You say your heart won – as if the heart is no place for reason or free will. That is not true. It is a romantic myth we allow ourselves. We like to sentimentalise our biology – which is to be selfish creatures genetically programmed to look after number one – and ignore our ability to make moral choices and rise above our genetic inheritance. We do not have to let feelings become reasons. Love may be a life force, but it can also be used as an excuse: “It’s not my fault. I am helpless in the face of my emotions.”

Love can also be a great get-out clause. Has your lover been honest about his unhappiness or truthful about how he came to find himself with two young children in a situation so intolerable he wants to leave it? I am not saying he is lying. Sometimes we sleepwalk into misery and become so overwhelmed that we stay in a toxic relationship that does nobody any good. One day, we may wake up and choose to do something about our situation. We do that for all sorts of reasons, and one of them may be meeting somebody and seeing a glimpse of intimacy and true understanding. But if that’s the truth of his situation, he must be honest and brave and deal with it. We must clean up our mess before we can start afresh.

If there is real love between you two and destructive unhappiness between him and his girlfriend, it might be better for all concerned – including his kids – if he left the relationship. But lying and cheating is no way to go. However terrible it may feel in the short term, ultimately it is kinder to tell the truth and end a relationship cleanly than to let somebody suffer a half-life of secrets and lies – which is what he is doing to his girlfriend. It is not fair; nor is it fair to involve you. His present relationship is none of your business.

Ask him to sort himself out, and get on with your life while he does. It could take weeks or months for him to resolve things. It may even be that he decides to stay with his girlfriend and kids. Either way, the best thing you can do is stand back. I know that’s hard, but if you really love each other and want to be together in an honest and healthy relationship, the willingness on both your parts to do the right thing will be a measure of the trust and understanding between you. You say your love is real. In that case, you have nothing to worry about.

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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