My life is sheer hell. I have been married for 22 years. We were happy, but our sex life was never really exciting. Then I met someone; a guy younger than me at work who has thrilled me with stories of his conquests and success with girls. My wife says he has changed me into a “horrible, depraved individual”. I am obsessed by him. He means more to me than anything. I'm not gay but bisexual, and I love beautiful, young things. I think he worries that we're getting too close and wants to leave his job to escape from me, but

I can't live without him. My wife is standing by me. She thinks I am mentally ill. Understandably, I am being punished. We sleep in separate rooms, so I'm locked in a sexless but loving marriage, more like mother and son. I need love and to be held; I need a fulfilling sexual relationship; and I'm trapped. I don't want to throw away my family life, but I know our sex life is not going to improve. I either continue as a family man in the spare bedroom or find someone for fun and lead a double life. Please help.

I am not surprised your relationship with your wife is that of mother and son. You sound like a 16-year-old. Everything you've written is an echo of that “I want it and I want it now” stage of adolescence. Actually, strike that. My teenager is way more mature than you. I am sorry to be unkind, but can you see how myopically self-centred you sound? It's all me, me, me: I don't get sex; I feel trapped; I need love; I want fun. Not a word of regret. No sense of sorrow for the pain you have caused. You have wounded your wife beyond belief. You are driving a young man out of his job. He doesn't sound depraved, he sounds like an idiot. Anybody who boasts of his conquests (the word says it all) and success with girls (women, surely, if they are over the age of consent?) hasn't made it past the nappy stage of emotional maturity. The question is why, at fortysomething, you find that even interesting, let alone exciting.

Your wife thinks you are mentally ill. That's a harsh way of saying you are completely unresolved, not simply about your sexuality, but also about your emotional needs. It sounds as though meeting this young man has precipitated some sort of psychic crisis, catapulting you back to a teenage self. People make jokes about the midlife crisis, but it is as painful as the turmoil of our adolescent years. These are the two most difficult periods of life.

If we did not resolve our emotional issues in our teens, as we struggled to make our way to maturity, it is likely that they will resurface in our forties, when we mourn the ending of youth. The midlife crisis is not a crisis of sex but of identity.

I'm not a psychologist, but it seems to me that you need serious help. If you have never resolved your issues around sexuality or emotional identity, it may be that you have been living a false life for the past 20 years. Living a lie is hard work. What we truly feel must eventually find expression. All those unfulfilled needs and desires are bursting out of you in a way that is both overwhelming and unmanageable.

Let's take your sexuality. You say you love beautiful, young things. Are you sure it's not simpler than that? You want to be a beautiful, young thing and cannot come to terms with the death of that possibility. Youth and beauty now belong to others, and no amount of sex or longing is going to change that. Usually, we grieve that loss and move on, but you can't move on. You have focused your intense need on a blameless stranger and now you're trapped in obsession. That's much more about you than it is about him. As for being bisexual, that seems to point to yet more confusion about identity. People may have both homosexual and heterosexual relationships as they search to discover their central beings, but most settle for one or the other. Many bisexual people struggle to make emotional commitments because they have no idea who they really are.

And that brings us back to the central issue, which is a crisis of identity. What should you do? You cannot possibly make decisions until you know who you are. Your wife is prepared to stand by you. Great. She is obviously a fantastic woman. If you really don't want to throw away your family life (and that involves what you both want, so your wife's needs are as important as yours), you need to decide what you truly want. To be a young boy who wants to be loved?

A teenager who wants to shag his brains out? Or a middle-aged man who wants to respect and honour his marriage? These are intensely difficult questions to solve on your own. Therapy will help. Do get some.

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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