In 2000, Nigella Lawson published the book that was so successful its title became both her nickname and the byword for her career: How To Be a Domestic Goddess. Britain had known plenty of celebrity cooks before, from the mumsy (Fanny Cradock, Delia Smith) to the macho (Marco Pierre White, Gordon Ramsay), but Lawson was the first one to suggest that baking cakes translated into a blissful home life. Lawson insisted her lifestyle was "normal" and that while the enviable kitchen on her TV show was not her own, those were definitely her real children darting in and out of the room, scoffing down ricotta cakes with grilled radicchio baked by their picture-perfect mother. This elision between fiction and reality confirmed her title: Nigella Lawson, domestic goddess.

It's hard to think of a sadder and more brutal undoing of such a high-profile image than what has happened to Lawson. In the past few days, she has gone from domestic goddess to the face of domestic violence, with her husband, Charles Saatchi, accepting a police caution on Monday night for assaulting her in front of Scott's restaurant in London. Part of what makes the photographs of the incident so shocking, in which Saatchi's hands are alternately around her throat and tweaking her nose, is that they look like a bitter public inversion of the idyllic private world portrayed by her programmes.

When printing the pictures, and reporting on the story, tabloids including the Daily Mail and the Daily Mirror made sure to include just how much the couple's house is worth, with the Mail taking its obsession with real estate to a self-parodic extent by adding how much Lawson and Saatchi had recently spent on renovations, beneath a photo of Saatchi's hand around Lawson's neck, her eyes full of tears and fear. In the meantime, the photographs are printed and reprinted. While on the one hand they draw attention to a serious problem, for the media they come with the additional aspect of showing a woman being assaulted and, as the popularity of murder mystery TV shows and a recent fashion spread depicting female writers killing themselves prove, one of the few things that seems to sell as much as sex is violence perpetrated against a woman.

Lawson and Saatchi have been photographed dozens of times sitting at that very same table at Scott's, eating peacefully, save for one bizarre photo from December that showed Saatchi clapping his hand over Lawson's mouth. One tabloid describes that moment as "playful", unwittingly anticipating Saatchi's later claim that the photos of him with his hands around his wife's throat merely caught them in the middle of a "playful tiff".

Some columnists have opined that part of the shock of this very sad story is that it is happening to a famous, successful woman: "Nigella Lawson ... isn't the sort of woman we expect to get hit by her husband," claimed one, beneath the headline Yes, it Can Happen to Her. I'm not sure what sort of woman "we" expect to suffer domestic abuse, but those of us who spend too much of our lives reading celebrity autobiographies are not quite as shocked by proof that domestic abuse is not solely "the grubby problem of the inarticulate and poorly educated, who can't eloquently express their frustration, who are not self-aware or emotionally intelligent enough to thrash out their differences via a civilised heart-to-heart, rather than simply with a thrashing". (Seriously, does anyone think that? Anyone?) The celebrity world may not offer much in useful instruction but one thing it does teach is that domestic abuse is not limited to a Roddy Doyle novel. Tina Turner, Lana Turner and, of course, Rihanna have all suffered from it and, just because they all had the means to leave their abusive partners, many of them stayed for some time. Practicalities are not the only factor in why some women stay with men who assault them.

The reactions to Lawson's assault – from customers at the restaurant craning to watch but apparently unwilling or unable to help, to the gawping paparazzi, to the astonished public, to the behaviour of Saatchi and Lawson themselves – all exemplify some of the problems in tackling domestic abuse. The reluctance of others to intrude on what may well be just a "playful" argument between husband and wife, and the fact that neighbours have since spoken up describing Saatchi and Lawson's relationship as "volatile", emphasise how hard it is to know when or how to intervene, and the powerful effect of retrospect. That Saatchi and Lawson are both famous doubtless makes intervention even more intimidating for many people. Saatchi insists he only accepted the caution "because I didn't want it hanging over us". Lawson has – as many women who have been assaulted do – remained silent.

Whether Saatchi's reputation bounces back as buoyantly as Chris Brown's has done, or is destroyed as Ike Turner's was, remains to be seen. Whatever Lawson decides to do next is her business alone, because she is not the "Nigella Lawson" image she helped to promote: she is a woman going through something that 25% of all women will endure. It turned out Lawson was more right than she knew: her home life was "normal", albeit probably not in the way she meant.

You can contact the National Domestic Violence Helpline online or on 0808 2000 247

• This article was modified on 18 June 2013. The original stated that How To Be a Domestic Goddess was published 10 years ago. It was further amended on 19 June 2013 to change the word "reticence" to "reluctance".