I kissed a really good friend’s boyfriend. I know she adores him, so the betrayal is severe. Yes, alcohol was involved, and yes, I feel truly awful, but the worrying thing is that there’s a pattern there. This is not the first time. I only kiss these men, I never sleep with them. I just want to give the illusion that I’m better than their girlfriends because I know, in reality, I fall short. Maybe I don’t know the pain of being cheated on. I’m 20 and have never had a relationship longer than three days; nor have I committed myself or remotely expected commitment. I’ve had “ugly-duckling syndrome”, which appears to have turned me into a monster. I could blame my difficult relationship with my father, mild bullying or low self-esteem, but maybe I’m just a bad person.

I never expect guys to love me, and feel patronised when they say they do. When I see girls who don’t try or make an effort, but are immensely loved, I feel angry and frustrated. I know someone I love will cheat. I hope it happens sooner rather than later, as I need to change. What goes around comes around.

I know I deserve it.

here’s not much point in beating you up for bad behaviour. You seem to be doing that very effectively yourself. A bit too effectively, really. There is an underlying tone in your letter that’s a little too dramatic to be really honest or sincere. Intuitively, I don’t feel you’re expressing regret so much as playing the drama queen: “Poor me. Bad me. Look how wicked I am.”

When children deliberately smash stuff or bang another kid over the head, they don’t do it because they’re having a laugh or a good time. They are testing the boundaries of other people’s tolerance by asking grown-ups just how far they can go and still be loved. I wonder whether you do these things, not because you’re a bad person, but because you long for unconditional love and forgiveness.

I know it sounds perverse, but there’s nothing like hurting people to get their attention. A sweet-natured exchange doesn’t do it in the same way. Hurt somebody and you know you will have their undivided attention for weeks, or even months. It’s not a pleasant sort of attention. It carries with it great sackloads of guilt and shame. So, why do it?

My feeling is that you’re terrified of intimacy and this is an elaborate way of getting close to people. Hate is described as the flip side of love because it is an equally powerful and commanding emotion. You admit to anger and frustration at the sight of girls being “immensely loved” without any apparent effort. In other words, they are simply being themselves. My feeling is that you don’t feel you’re good enough to be yourself, so you have to find an identity. The one you’ve found is “bad girl”. I’m not sure that’s low self-esteem so much as no self-esteem. Why do you think you deserve no more than a shameful fumble in a dark corner? It is just so sad. You need to bring yourself out into the light and act in ways that are honourable. When we do things that are estimable, we feel estimable.

More intriguingly, why feel patronised by somebody telling you they love you? It’s such an odd word to choose, unless, in some way,

you’ve been trained to believe that love is insincere or a way of gaining power over somebody. At the same time, you long for it. Of course you do. We all do. We are, by nature, designed to be in relationships, so I wonder if that dichotomy comes from a difficult relationship with your father and a long history of trying (and failing) to get his love and attention. If the effort you had to make to get him to love you was huge, seeing love handed out without a price tag may well fill you with rage. As children, if being ourselves gets no results, we try another way, such as acting up and rebelling.

As for being cheated on, I wonder if it will simply reinforce your cynicism and lead you down the road of “See, I told you love was rubbish and all men are bastards”. That road goes only one way — to sterile loneliness. Wanting to be cheated on as a form of aversion therapy also suggests you can allow yourself to become vulnerable enough to love and to be hurt, which doesn’t seem the case at the moment.

Can I appeal to you to try and grasp the simple fact that you are lovable? We all are, if only we open ourselves up enough to allow it to happen. You don’t have to stand on your head (or kiss furtively in corners) to get attention. You are old enough to understand that your father is flawed and human, and that his opinion (or anyone else’s) is just one among millions. You don’t have to live by it. You can be your own person. If that seems too hard, go to your GP and ask to see a counsellor. You need help to counter your self-sabotaging behaviour. Life is a simple exchange. So is love. And so is happiness. We get out what we put in.

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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