We now know that women live an average of seven years longer than men. By that token, we should all be hitching our wagons to younger bedfellows; but we don't.
You could discuss the sociological, historical and anthropological reasons for this until the end of days (which will presumably only be populated by women, as all the men died a week earlier), but it really boils down to one truth; men are just a bit . . . well, rudimentary for want of a better word. When your mum comforted you (aged 13) over your first heartbreak by telling you "girls are just more mature than boys", she was absolutely right.
What she didn't tell you is that the boys never catch up.
Men and women have instinctively different attitudes to relationships and, despite re-runs of Sex and the City trying to convince us otherwise, it's okay to admit that men are driven by sex more than women.
It doesn't make us unequal, it's just biology. Actually, if anything, it makes us the more logical and rational gender as we our not slaves to our penises (there's a sentence I've always wanted to type).
A well-known musician (I'm not going to tell you his name) told me a while ago that he had consciously waited until his mid-40s to settle down and start a family, as he knew he probably wouldn't be faithful if he didn't wait until he was sure he wasn't 'missing out' on anything else. I admire his honesty, and there are so many notches on his bedpost at this stage that I'd say it is little more than firewood -- the time was right.
I think many men feel this way, but it's just not the done thing to admit it.
It's the reason that men will continue to pay money to watch women take their clothes off or swing around a pole, and the equivalent for women -- if we are honest -- is in the novelty camp, along with shoes for dogs and ice-cream makers.
The argument for equality sometimes overlooks these differences, but it's not letting your gender down to admit to not having a voracious sexual appetite or forgetting to think about sex hundreds of times a day.
Of course, marriages and relationships take work on both sides, and no one is saying that it is expected or acceptable that men will stray, but as a women, you need to understand these inalienable truths -- hooking up with a much younger man may be asking for trouble.
When the eternally gorgeous Demi Moore hooked up with the eternally irritating (and 15 years younger) Ashton Kutcher, it wasn't the age gap that made me think it wouldn't work. It was that Ashton admitted to lusting over Demi when he was 14.
Add to that the fact that Demi's daughters had posters of Kutcher in their bedrooms (presumably from his seminal acting days of Dude, Where's My Car?), and it's pretty obvious that the other big thing on the wall was the writing.
Personally, I would never have left Bruce Willis; I would have clung on to him for dear life like one of those torn, sweaty white vests he wore so well in the Die Hard movies . . . I digress.
Demi made the fundamental mistake of forgetting her mum's advice. Ashton just isn't grown up enough for a woman like her; add to that, in the job he does, he is constantly surrounded by temptation and his relatively young years, and it doesn't bode well.
The most offensive part of all of this is the speculation and gossip, the implications that Demi is too old, too 'made-up', or can't compete with whatever twentysomething-year-old model is pursuing her husband this week.
None of this is true.
She is gorgeous, sexy and engaging regardless of her date of birth.
If I were Demi, I would turn things around and tell Ashton that the past six years were an elaborate episode of Punk'd. Well, he should have known she was way out of his league. Send him a poster of Striptease for his wall.