Debate: If you were Jerry Hall, would you have Mick Jagger back?

Jerry and Mick are in trouble again, as one supermodel after another pops up to claim intimacy with the veteran rockstar. Should Jerry sling him out? Must an affair mark the end? No, says Jeremy Atiyah, there are worse things a partner can dump on a relationship. But infidelity is a betrayal of trust, says Virginia Ironside, and that's hard to come back from

Why stake an entire relationship on some narrow definition of fidelity? asks Jeremy Atiyah

When my wife told me she was having an affair, it didn't feel like the end of our world. She told me that I was still the main person in her life and I believed her. What mattered to me was how she felt, not what she had done.

I knew that if the movies were anything to go by, this situation should have developed into an enormous and slightly enjoyable drama. I, the faithful one, should have felt betrayed. I should have demanded my pound of flesh. I should have seized with great relish the opportunity to play the role of the wronged partner. At the very least I should have given my partner some kind of ultimatum: leave home now, or stop seeing that man.

But blow me down, life turned out to be more complex than that. I sat there thinking how unique every infidelity must be, and how useless the movies were. Neither I, nor anybody else in history, had ever been exactly here before. There was no obvious response. Was I really the wronged partner? Perhaps my partner was having an affair because she felt like the wronged partner. I wasn't sure. Neither was she.

In fact I hardly gave separation a thought. I didn't want it and my partner didn't want it. She had a problem with the progress of her life and was expressing it. Perhaps she even deserved credit for this. Who could tell? She had broken the emotional log-jam of our not particularly exciting marriage. Perhaps that was what was needed. For me to enforce a sudden split would have been a ludicrous act of petulance, a totally disproportionate and self-defeating reaction.

We live in experimental, changing times. Who can honestly say that they know exactly where they are going? What is fidelity? Why stake an entire relationship on some uncompromising definition? There are far worse things that people dump on their partners than infidelities. Private neuroses, abuse, blackmail, bullying, manipulation and deceit for example. My partner had given me none of these, nor had she done anything to deserve them.

Who was I suddenly to start laying down the law in such a simplistic, brutal way? I did not want to subject the infinite complexity of our relationship to neanderthal social rules invented by other people. I was certainly confused but so was my partner. I felt that this was her crisis just as much as mine. In fact it was our crisis. The first evening after she had told me about the situation, we sat together with our chins in our hands and tried to think.

What we needed was time, not deadlines. If possible, time together. We needed to find out what it all meant. And by seeing the problem from the same angle, we did come closer together. We spent more time talking more openly than we had for years. She talked about the difficulties of her affair and I listened sympathetically. She deserved it.

I'll be honest. A couple of years later we did split up. Ah! you say: the affair! It must have inflicted irreparable damage, it must have left behind its poison! But I say that affairs are what married people do. Whether or not an affair means infidelity is up to you.

Jeremy Atiyah is

travel editor

of the

`Independent

on Sunday'

Infidelity hurts people, says Virginia Ironside, and it can be hard to forgive such betrayal.

"It was like a glass made of crystal shattering into a thousand pieces," wrote one woman to me when her husband had had an affair. "However hard you tried, you could never put it back together again."

What most couples find most hard to bear, when their partner has an affair, is the breaking of trust. It's not the actual sex they mind so much about; it's the breaking of a commitment to each other. If they're married, they've made their vows in public. Fidelity is one of the promises they've made to each other. Fidelity is usually crucial.

It's the breaking of trust that makes women say to their partners: "If you do ever have an affair, I don't want to know about it." It's as if they're saying, go ahead, sleep with the odd person if you like, but the moment you let me know or I find out, the balloon will go up.

Apart from the lack of trust, anyone who's had a partner who's had an affair will know of the terrible effect it can have on their sexual self- esteem.They question whether they're attractive any more to their partners. They feel like dreadful sexual lumps of nothingness. Their sexuality has been drained by the affair.

But affairs are usually the tip of the iceberg. As marriage counsellors know, they're rarely had out of context. Nearly always they signify that something far deeper is wrong with the relationship than sex. Frequently someone will have an affair when things are going terribly wonky at home - a disastrous way to try to put things right, of course.

Affairs can hurt children too, who may be unwittingly be drawn into the whole grim business. I remember going away on holiday with my mother to France. She made friends with a tall, dark handsome Frenchman and suggested I didn't mention him to my father when we returned, but being only eight, I blurted something out by accident. My father didn't speak to my mother for a week; she didn't speak to me for a day. I felt in some horrible way that it was all my fault.

Then, often, other people will know about the affair when you're left in the dark. "I felt such a fool when I told my best friend about it," wrote one woman. "She said she'd known for years. `But why didn't you tell me?' I said. `We didn't want to hurt you,' she said. But the idea my friends knew and had kept it secret was far worse. I felt so humiliated."

It's been said that an affair can add spice to a partnership. And it's true that if an affair forces a couple to address the issues that are going wrong, they can become closer. But it's terribly rare. Having an affair to gee things up is rather like building a bonfire in your sitting room to generate more heat. True, it'll warm things up. But usually it will burn the house down as well.

Virginia Ironside is `The Independent's agony aunt.