The end of a marriage is a lonely, painful experience and it is human nature to take whatever comfort you can along the way.

However, unless you or your husband are completely sexually opportunistic, the behaviour you describe suggests real emotional confusion about what you are about to do.

Susanna Abse, a psychotherapist and the director of the Tavistock Centre for Couple Relationships (www.tccr.org.uk), wonders “if this pattern of fighting and then getting close is an old one, possibly based on shared fears of either getting too close or getting too distant”.

She also suggests that “your husband's affair and being separated means that those fears are being played out at a much more intense pitch than before”.Since fear heightens arousal, that would, I suppose, explain the great sex. In 1974 the psychologists Donald G.

Dutton and Arthur P. Aron conducted “the shaky bridge” experiment, which established that when a female approached men and asked them to fill in a questionnaire on a rickety bridge swaying 230ft over a river, they provided much more sexualised content than a control group on a stable bridge over a 10ft drop. Similarly, people are more responsive to sexual come-ons after riding rollercoasters.

While channelling strong emotion into sexual attraction may provide a form of relief for you both, it is a destabilising way of alleviating tension. Your children must wonder why daddy sleeps over and you must question why you can have great sex, yet you can't have a relationship.

You say that you have already tried counselling, but I suspect that you were too bitter about his affair to really engage in the repair process. Chances are you were having problems before he cheated, but according to the Gottman Institute, the average couple waits six years before seeking help for marital difficulties.

The likelihood is that by the time you got to counselling the focus was on his infidelity and not on the issues that may have triggered it.It is often easier to blame a partner's infidelity, or a generic cause, such as lack of “communication”, than it is to admit individual responsibility for the failure of the marriage, and unfortunately, once divorce is on the table, it has a tendency to create its own momentum. It is seen as the solution, the end of all the problems, but really, it is only the beginning.

As any divorcée will tell you, it is only after the dust has settled that the loneliness, the angst and the inconvenience hit home. Like most decent parents, you will make your children's wellbeing the priority so you will bite your lip while you make a U-turn to collect their forgotten homework.

If you are really lucky, you will meet someone else and it will be great. Every other weekend. But then you'll find yourself facing the unenviable task of explaining why he is sleeping on daddy's side of the bed. And it's not just hard for women. Australian research into the effects of marital separation on men found that they still reported strong feelings of anger at having been “left” by their ex-spouses ten years after their divorce.

Clearly there is good cause for many divorces, particularly for children living in high-conflict, abusive or addictive households. However, in a US report in 2002, “Does divorce make people happy?” 86 per cent of couples who had contemplated divorce but stayed together described themselves as considerably happier five years later.Though it takes a brave, mature and forgiving adult to raise the white flag in the middle of divorce negotiations, the alternative is a bit like drinking poison and hoping that your husband will die. So be brave.