For me, that realisation dawned on the morning I woke up with flu and found that my wife was not going to look after me like my mother had. Rather than adopting a blanket policy of brow-soothing and Ribena-bringing, throughout my illness she maintained a faint but unmistakeable air of irritation, as though I had somehow deliberately gone out to attract this virus.
But surely men don't want mothering from the modern-day woman? Surely they're looking for a one-to-one, look-me-in-the-eye relationship with an equal who happens to be of the opposite gender? Don't you believe it. "Men's expectations are still that they will be looked after in the ways their mother looked after them," confirms Janet Reibstein, presenter of Channel 4 series Love Life. It may no longer be considered acceptable for the man of the house to come home and bellow "Where's my tea?," but there are few males who don't want from their wife the approval, admiration and general oh-dear-have-those-boys-been-horrid-to-you-again head-patting that our mothers used to dispense so effortlessly.
Ironically, of all the bits of anatomy that first attract us to a woman, it's the ear we end up most wanting to have. Forget the sex - a goodbye kiss on the cheek will do. Why, one American insurance company found that men whose wives had kissed them before they drove off to work were 50 per cent less likely to be involved in a crash than their unpecked counterparts.
Essentially, men want to be married to a pal with breasts. Ask yourself, though, whether such low-level emotional ambition would be enough to satisfy the average woman, gingered up by a good decade's worth of What Do You Want From A Relationship-type articles. The answer is a loud "no". While men's expectations of marriage have remained much the same, women's have changed dramatically.
A Fifties housewife might list children, financial support, to be married forever and to be looked after as her top priorities. Nineties woman, financially independent and not necessarily interested in children, would probably regard companionship, equality, domestic help, respect for her aspirations and career and good sex as the basic minimum. No wonder the sexes find it difficult to accommodate their respective needs and desires.
Neither sex, however, are above a bit of cake and eatism. A ring round my female friends produced a fairly standard list of demands. What most of them seemed to want from a husband was general anti-lonely insurance (ditto men), plus a father for their children and a general sounding-board for their problems. So far, so good. What about the details? What kind of personality were they looking for? "Strong" was a word which featured prominently. But how did they define it? "A strong man is one who is in touch with his feelings and not afraid to express them," said Caroline, 32, a graphic designer, echoing the words of several others. But would she like to see her man cry? "Yuk, no," came the reply. "It's such a turn- off."
The other contentious item on the wish-list was "security". Having established that this did not mean a man in a Group Four uniform, it soon became apparent that "security" meant "money". "I don't expect to stay at home and let my husband provide for me," said Diana, 29. "But I do expect him to be able to keep us going financially when the time comes to have children."
Men are also torn between two versions of womanhood. There's the wife that stays at home with the kids and welcomes her harried husband back to the peace of the domestic hearth. The downside is that the family must subsist on one salary and the wife is often frustrated and bored. Then there's the wife who shoulders equal financial responsibility and goes out to work - but neither partner sees much of the children and both are tense and cross at the end of the day. "Conflicts like these will only be resolved," says one female friend, "when husband and wife are able to work shorter or more flexible hours. That way a husband will be able to spend longed-for time with his children, and his wife won't have to make some hideous choice between keeping her mind and leaving her kids, or devoting herself to her offspring and screwing her career."
These days, of course, most men and women espouse the notion of 50:50 sharing, both in terms of cash and household chores. Not so in my mother's day. She had so little to do with domestic money matters that when my father died, she was completely at sea. Her dependence on him was brought home with painful vividness when, having dutifully informed the bank of his death, she spent the following two weeks getting to supermarket checkouts and finding her credit cards coming up invalid, because she was only classed as a "secondary" user.
But surely things are different among couples who got together in the Nineties, rather than the Fifties? Not as much as we might think. "With 90 per cent of couples, the person who has the higher income is the man, and the person who does the greater share of the housework is the woman." So says Dr Robin Russell, a marital psychology lecturer at Goldsmiths College, London, who has pioneered a marriage questionnaire which gives couples a detailed read-out of their compatibility rating.
Dr Russell is an enthusiastic supporter of pre-marital instruction of the sort provided by the Catholic Church, whereby all would-be brides and grooms are required to attend up to four fireside chats with the priest. As well as alerting couples to the possible surprises of marriage, these courses aim to eliminate more everyday inter-sex misunderstandings.
I would have liked someone to point out to me where I was going wrong in my assumption that with my manly, problem-solving approach to life, I would be able to free my wife from the endless treadmill of talking things through with her friends. It is only recently that I have come to realise that she positively enjoys the circularity of these conversations - and that when she tells me about a problem, she wants just a sympathetic ear, not a taskforce.
Given that the sexes speak different emotional languages, it is hardly surprising that arguing is such an integral part of marriage. However, according to Prof Michael Argyle, Reader in Social Psychology at Oxford University, it's good to talk, even if it is at full volume. "A couple may have some very happy and rewarding times, as well as a lot of rows," says Prof Argyle. "Marriage is the source of a lot of conflict. However, it is perfectly possible to enjoy a great deal of satisfaction at the same time."
And not just satisfaction, but improved health, too. A study in the American Journal of Sociology and Health found that single men were three times more likely to suffer mental disorder than their married counterparts (1.74 times more in the case of women). Having made a detailed study of 1,300 different couples, Dr Russell goes even further. "Being unmarried is a contributory cause of cancer, comparable to smoking," he claims. "In whatever country or culture you live, your marriage is by far the most important factor in determining your happiness and well-being - far more so than how you are doing at work. Your domestic environment dictates your mood far more than your working one; it defines you, whereas your job merely occupies you."
That's not to say being married is easy, as demonstrated by the fact that four out of every 10 marriages now ends in divorce. According to Julia Cole of Relate, what has made marriage particularly hard to maintain is the way in which it has changed from being a public duty to a private arrangement. "Marriage used to be very much an institution, something that involved a wider community of friends and family, and was linked to considerations of property and economics. Today the focus is far more on the couple's relationship and what they each want out of it. There is less cultural back-up, less support from the wider family - it's just the two of them out there on their own."
Sounds like hard work. So why do so many people still take that firewalk down the aisle? "Every research study shows that the vast majority of people are looking for one loving, secure relationship; for the chance to give love to - and be loved by - one person," says Cole. "And even though social conditions may have changed, it's the same personal qualities that make a marriage work today which have always made it work: care, patience, love, a sense of getting though the bad times as well as the good and an ability to deal with issues rather than flying off the handle."
In other words, there should be something solid between a couple. It's not so easy, though, in an age when concrete gender stereotypes are generally regarded as unsafe structures to live in. "I expect her to have a career and look after the home; she expects me to do the same," confides one male friend. "As a result, we are forever bickering over who does what. Sometimes, when we are arguing over whose turn it is to make the dinner, I can't help thinking how much easier it must have been in the old days."
Ah, yes. But so much more unfulfilling, argues Reibstein. "Sure, it's harder work making a marriage succeed these days, but when it does work it does so on a far deeper, more personal, level," she says. "What men and women are going through at the moment is confusion, sure, but I don't think it's unconstructive confusion."