Marriage lesson one: divorce

Finally, reality is kicking in: most relationships do not last for ever. We need to learn to deal with separation and starting again

One of Freud's most interesting observations is a throwaway line: "As a rule, second marriages turn out much better". This was written in 1931, at a time when divorce was uncommon enough to raise eyebrows and result, in some cases, in social ostracism. Yet Freud had put his finger on the central flaw in marriage as we know it, the assumption that it is for life. You would think, with two out of five marriages ending in divorce, that the unreliability of that expectation had been demonstrated beyond argument. But how people live and how governments would like them to live are different things. Four years ago, John Major's administration published a divorce Bill which opened with the confusing assertion that "the institution of marriage should be supported". So the news last week that Tony Blair's government wants children to be taught how to cope with separation, divorce and "re-partnering" is little short of a revolution.

The new direction is revealed in a leaked draft of guidelines on parenthood education, which stresses the importance of stable relationships but recognises that marriage is only one model for adults. Lessons in "21st-century parenting" should include single-parent families and homosexual partnerships, it suggests. Apparently the Education Secretary, David Blunkett, wanted greater emphasis on traditional households, but a cabinet that includes three gay men is well-placed to know that heterosexual unions are not ideal for everyone.

The reaction was immediate and predictable. "We don't want to teach children that divorce or breaking up are normal or good," protested Julian Brazier, president of the Conservative Family Campaign. But that is just what divorce is these days: an everyday event which may be painful at the time but is often the best way out of an unbearable set of circumstances. And that situation is very different from the one our grandparents found themselves in.

Those of us who were born in the second half of the 20th century are unique in belonging to the first generations who can realistically expect marriage to last 40 years. In the 17th and 18th centuries, the median duration of marriage was between 20 and 30 years for the aristocracy, 20 for the poor. It was only in the 20th century that this began to change, especially in the post-war period when the NHS delivered increased longevity.

How many of us can say, hand on heart, that we welcome the prospect of four decades with the same person? And I mean staying faithful to them, as well as continuing to enjoy their company. What this does not allow for is the way we change as we grow older, discovering new interests and mixing with different people. Sometimes love lasts, but just as often it changes to friendship or even indifference.

Freud thought first marriages fell apart because of disappointment and "the accumulation of occasions for aggression". As we get older, we get to know ourselves better and are less likely to make the same mistakes, although there are always glaring exceptions such as Bill Clinton or the Mayor of New York, Rudy Giuliani, who separated from his wife in complex circumstances last week. Serial relationships, instead of being an admission of failure, seem to me a natural way to live.

At this point, somebody usually raises the question of children. This is fair enough, although it is another aspect of family life which gets measured in relation to a mythical past. The children of separated and divorced parents are not experiencing a degree of disruption unknown to previous generations, but repeating an old pattern. The difference is that their parents' separations tend to be voluntary, on one side at least, where in the past they were caused by illness, accident or war.

While it is true that children prefer their parents to stay together, the non-availability of divorce in previous centuries concealed a great deal of domestic misery. There are many ways of damaging children, including the parental coldness and distance that were until recently the norm in upper-middle-class families. I am always amazed by the readiness of public-school-educated politicians, who were banished from their own homes at the age of seven, to criticise single mothers who are doing their best to look after their children in spite of having very little money.

Now that divorce and "re-partnering" are here to stay, it is sensible to look at how we can take some of the bitterness out of separation, and one way of doing it is to prepare children for the possibility while they are still at school. Another is to remove the "till death do us part" element from adult relationships. What makes divorce so hard for some couples is the knowledge that they vowed to stay together in front of all their family and friends. That is why so many divorced people decide to cohabit second time round, instead of making extravagant promises they might not be able to keep.

The other problem that needs tackling is gender-specific. Men are, on the whole, terrible at leaving relationships. They tend to get into the kind of mess epitomised by Mr Giuliani, involved with another woman (or two) and unsure whether they are seeking a diversion from their marriage or to leave it. One friend of mine suggested a trial separation to her husband and subsequently discovered he had managed on his own for all of two hours. I don't think men behave like this because it's in their genes but because they know they can get away with it.

This is one instance where indecision, usually regarded as a feminine trait, is disproportionately displayed by men. Maybe they like having their cake and eating it, so to speak, but I also believe it has to do with the near-universal masculine terror of living alone.

Mr Clinton, astonishingly, attracted public sympathy as soon as his wife went off to New York to pursue her own political ambitions. He is now said to be sleeping with his dog, an evolutionary advance of gargantuan proportions in comparison to his previous behaviour.

A critic writes: a procession of anxious friends has been turning up in the last few days with exactly the same problem. They have not been able to finish a novel by Martin Amis, or the extracts currently appearing in newspapers from his memoirs, and worry that there is something seriously wrong with them. They fear they are out of step with the zeitgeist and will no longer be invited to fashionable dinner parties if their secret is discovered.

Fortunately I have been able to reassure them. These are actually robust signs of mental health, especially if symptoms include a conviction that the work of Mr Amis's late father is not all it's cracked up to be either. As a rule, I am also advising female friends that they should not accept a second date with any man who boasts that Money made him laugh aloud or that London Fields is his favourite novel. Next?