Liz Hoggard: The great Sam Taylor-Wood dilemma

Every night it's the same conversation. All women seem to want to talk about is artist Sam Taylor-Wood and her toyboy. Taylor-Wood, 42 – who has handled cancer (twice) and a marriage split with dignity – is something of a role model. She hangs out with A-listers, but never forgets her roots. She looks fantastic, but not unrealistic. She strikes you as a girl's girl.

But now here she is stepping out with a 19-year-old actor. And not just any actor – Aaron Johnson was who she cast as John Lennon in her new film, Nowhere Boy. Just to make the scenario more delicious, Taylor-Wood's ex-husband, art dealer, Jay Jopling, 45, had his own May-December romance – dating Lily Allen, 23, last year. Was it an act of revenge? Or did they both feel the need for new young flesh?

The difference is in the reporting. When Jopling was pictured frolicking in the sea with Allen, headlines were playful rather than censorious. It was a bit like watching your Dad make up for lost time. And frankly Lily always has the last word – her terrific new album, the confessional It's Not Me, It's You, must have had ex-boyfriends quaking in their boots. Never mind an old Etonian, 22 years older.

But Sam is different. We care passionately. And women's attitudes are wildly divergent. Is she a liberated sexual heroine – after all, a fling with a teenager is the perfect way to get over a marriage split (silly to tie yourself down with a grown-up when you're still processing it all). Or is it just plain wrong on every level? Sexually, morally, professionally.

Where you stand on Sam seems to depend if you define yourself as a mother or a lover. "I just feel protective of that young boy," a PR with twentysomething sons tells me. "Nonsense," disagrees another mother. "It will be the making of him."

A lot of late-night wine has been spilled over this one. "What on earth does she see in him?" asks a friend's teenage son crossly. He seems to take it personally she didn't choose him. Of course young men have always relied on older women for their "sentimental education" – just look at new movie Chéri.

I'd argue that every woman over 40 needs a man she can take to parties, who will laugh at her jokes, remember which cocktail she likes. You don't automatically sleep together (many of the best walkers are gay) but it might be quite nice if you did. Such is the prevalence of the "pragmatic" relationship, there is even a name for the sexually voracious older woman: the urban cougar. Think Sharon Stone, Kim Cattrall, Madonna.

But should the cougars be more scrupulous? Is feminism being distorted by women who are behaving as selfish indivualists? This week American columnist Linda Hirshman huffed about a new generation of "Jezebels" who promote the idea that feminism is simply "doing what feels good".

It's a thorny issue. But women have come late to pleasure. We shouldn't stop now. I wouldn't pay for sex. But I would – and do – pay for good company. Invites, careers advice, nice restaurants, why not? It's what older men have always done with younger women. Johnson will learn a hell of a lot from Taylor-Wood. And I'm not talking about sex.

So Sam, go girl! On the other hand: have you learned nothing in the last 40 years of your eventful life? What the hell will you talk about with a 19-year-old?