A couple put their arms around each other and move in close for a heartfelt kiss. She tilts her head and closes her eyes; his are open, looking at her with protective devotion.

They seem happy in each other’s company, clearly lovers and good friends, comfortable with each other and in their own skins.

So far, so touching. But equally, so what? The red-carpet shot published in the Mail this week is nothing exceptional, surely… save for the fact that he is Keanu Reeves, the 58-year-old film star – and his girlfriend, Alexandra Grant, is not only 50 but has grey hair, too.

Yet shock – even horror – is expressed every time a new picture of the couple emerges.

People can’t seem to get over the fact that a heartthrob is dating a mature woman, rather than a lithe young girl with puffy lips and a spookily immobile face. (Grant’s grey hair always gets a mention in the press coverage.)

What is it that bothers people about this relationship? Is it their similar ages? Is it that, while she is a handsome woman, she is not conventionally button-nosed pretty? Nor does she appear to have had cosmetic tweakments to make her look like every other woman in Hollywood.

Grant may be a successful artist who is trilingual, teaches and is a regular doer of good philanthropic things. But where are the boobs, hips and lustrous long hair that suggest she could squeeze out five kids in as many years and do the Pirelli calendar?

Hot babes are male accessories like big watches and fast cars

That juicy, youthful, fecund look so many women seek to emulate long after that particular evolutionary asset has gone.

For it is a truth universally acknowledged that a hot rich guy should forever be in want of a younger, hotter wife. Unless she has been married to him for aeons, we’ve been indoctrinated to believe that a middle-aged woman just doesn’t sit right with a middle-aged male icon.

I admit I’m a serial offender. If ever I see a male celebrity with a ‘normal’ woman, I’m amazed and almost appalled. It’s not that I’m against it, just that it’s so rare, like albino tigers or Lib Dem MPs. Yet at the sight of another old git posing with his ultra-polished arm candy, I just sigh.

I blame male vanity. Insecure men need validation of their own significance, so young, hot babes are as much an accessory to their ego as big watches, noisy cars and all that bellowing about their assets.

According to statistics, women stress about going grey, men about going bald. But when women go grey, they don’t start dating someone half their age.

High-profile men such as Keanu Reeves, who refuse to conform to these ‘common standards’, are the exceptions that prove the rule.

Pierce Brosnan, 69, is another. He defended his wife of 30 years, Keely Shaye Smith, 59, from fat-shaming trolls recently with these words: ‘Friends offered her surgery to reduce her weight. But I strongly love every curve of her body. She is the most beautiful woman in my eyes… and I am very proud of her, and I always seek to be worthy of her love.’

Brosnan and Reeves have something in common that might explain why they are among the more evolved males of the species. Brosnan’s first wife died of cancer, while Keanu’s ex, Jennifer Syme, died in a car crash in 2001, aged 28, shortly after they lost their first child to stillbirth. The tragedy and his grief deepened his distance from the looks-obsessed inanity of Hollywood.

I met Keanu Reeves a couple of times in the Nineties when I was researching a piece for a magazine. It was a crushingly embarrassing story for which I had to behave like a superfan (stalker, more like). My editor said, get out and meet him, which I eventually did.

The man I found clearly did not believe the hype that surrounded his starry career and longed for a normal life. It doesn’t surprise me that today he feels no need to assert his masculinity by having a babe at his side. He is an oasis in a desert of emotionally shallow male narcissists.

Keanu didn’t believe the hype about himself

Of course, if women were a bit braver about looking their age, men might be forced to change.

Alexandra Grant attended a celebrity-packed dinner party in Beverly Hills shortly after their relationship was revealed in 2019, and said beauty was ‘something you can see with your eyes closed’.

I wish — but it’s a laudable sentiment and it went down well with the stellar attendees. Yet none of them had let their hair go grey.

Demi Moore, then in her late 50s, had Morticia Addams-like jet- black hair. The rest were in their late 40s: Gwyneth Paltrow with quiet, tasteful, East Coast American honey hair, Kate Hudson and celebrity stylist Rachel Zoe both with the sexier West Coast blonde locks that spell youth.

Because let’s not pretend that when we see grey-haired female stars on the red carpet, we don’t notice it. We do — and perform a mental assessment of their sex appeal. Grey hair shouts that you are sexually past your fertile prime (the model Erin O’Connor went grey for a while but I notice she has returned to black. One wonders, did the work dry up?)

It’s still not really OK until you are ‘old old’. The truth is, a lot of us will die with hair that hasn’t been allowed to go grey.

My mouse-brown hair was red when I spotted the first grey hair, then a lush brown, then blonde. Endless shades of blonde. The reasons I let go of the façade were cost, time and the fact that I was finding it increasingly hard to be convinced by it myself.

Abandoning the hair dye was, in a way, also the abandonment of my ambition to achieve textbook sexual attractiveness. I was almost saying: ‘I give up. Yes, everybody, look at me, my ovaries are useless. Perhaps I am too!’

My boyfriend – a younger man, if you’re interested – just lets me get on with life, but occasionally he might ask me if I want to dye my hair again — once, when he was drunk, he even asked if I wanted to have a boob job. No thanks, I said.

Is he joking? He says he likes my grey hair and the way my body has changed, but I’m not sure how I feel about it. We women live in a world where we are never good enough. Maybe we are worse than men at judging our looks against what we see on red carpets.

Indeed, our reaction to Keanu and his girlfriend Alexandra tells us so much about our own prejudice and, actually, nothing about the happy couple. One of Alexandra’s circle, the writer Elise Loehnen, has said her friend is ‘so much more than her hair colour and her famous life partner’. Elise is right. Alexandra looks like someone who thinks she is enough.

What is truly shocking about a picture of a loved-up couple of fiftysomethings is that we – including me – give a fig about it.

For all people’s talk about equality, we have barely budged on this debate. It’s a little bit more accepted in Hollywood for women to look older and greyer, but no matter how many kisses Keanu and Alexandra exchange on the red carpet, our attitude to natural ageing is still one of disgust.