When Valérie Trierweiler entered the Elysée Palace on the arm of France's first socialist president for 17 years, her desire to help François Hollande succeed was matched by a fierce resolve never to be seen as a trophy wife.
"I want to represent the image of France, do the necessary smiling, be well dressed," she told a British newspaper, The Times, soon after Hollande was voted into power by a French electorate anxious for change. "But it shouldn't stop there. I will not be a potiche [literally a decorative vase]."
Strong willed, well educated and politically astute, she had a career of her own. She very much wanted to keep it, in defiance of a sizeable slice of public opinion that regarded being a journalist and première dame at the same time as a recipe for trouble.
Barely six months into the Hollande presidency, there has been trouble in abundance.
Trierweiler has at times resembled the loosest of cannons, its projectiles hurtling off to inflict real damage on a head of state already struggling with what he admits is an economic crisis of exceptional gravity.
A description of her as an "unpinned grenade", attributed in a new book released this week to the billionaire owner of Paris Match, the glossy news magazine for which she still works, is a logical extension of the battleground metaphor.
In her determination to avoid being written off as a potiche, Trierweiler has reinforced the views of critics convinced that her twin roles represent a powerful conflict of interests.
Members of her own journalistic trade have said the case for a discreet withdrawal from media life would have been overwhelming even for a first lady who commanded trust as a model of diplomacy and restraint.
Trierweiler is not that kind of woman. She speaks her mind, not always thinking about the likely repercussions or, on a more mischievous interpretation, thinking them through with some relish.
She cares little for reputations. She was a young political reporter when the notorious womaniser Dominique Strauss-Kahn, then a socialist minister, told her she was the prettiest journalist in Paris. Her withering response, much-repeated in recent months, was: "I thought that was Anne Sinclair [the television presenter he married in 1991]."
Two decades later, Trierweiler, 47, twice married with three children, still finds it hard to conceal her true feelings.
She is not married to Hollande but, as his partner, she's France's first unmarried première dame. It is a relationship complicated by her long-running feud with Ségolène Royal, a former presidential candidate and the mother of Hollande's two sons and two daughters.
Among the unflattering portraits presented by unofficial biographers, she has been depicted as "a cocktail of jealousy, vengeance and political calculation". This, taken from Entre Deux Feux (Between Two Fires) by Anna Cabana and Anne Rosencher, may seem harsh. But it is the kind of jibe that has reinforced an unfavourable public view.
Even when three French magazines were fined for publishing photographs showing Trierweiler in a bikini during a summer holiday, the judge observed that she had not always shown discretion in her private life.
Hollande's partner began life as Valérie Massonneau, the fifth of six children in a family settled in Angers, a pleasant town set among the majestic chateaux of the Loire Valley. Her paternal grandfather, whom she never knew, had been a banker, but her upbringing was modest. Her father, who lost a leg when he stepped on a German mine as a boy of 12 at the end of the Second World War, had only his invalid's pension and died relatively young. Her mother made ends meet as a cashier at an ice rink.
Fascinated from childhood by current affairs and journalism, Trierweiler studied political and social communications at the Sorbonne before joining the periodical Profession Politique and then Paris Match, where she specialised in covering the French Left. She has also presented television programmes on politics, but abandoned a project for a new series of documentaries as controversy grew over her twin roles.
The portrayal of her as an employer's headache appears in a new book by the journalist Jacqueline Rémy on the life of the Paris Match owner, Arnaud Lagardère, who also has wide-ranging industrial interests including aerospace and defence supplies.
In Arnaud Lagardère, The Heir Who Wanted To Live His Life, Rémy recalls asking him whether employing the first lady was an advantage. She says he replied: "Are you joking? Up until now, she's caused us nothing but trouble."
Rémy writes that Lagardère also talked of not wishing to renew her contract in December. She quotes the tycoon as saying he saw a need to avoid the same conflict of interest, between her work as a journalist and her role as the president's partner, identified by others.
But the book also points out that in a subsequent meeting with the author, he appeared to have changed his mind, having been persuaded by Hollande that she was "not really a first lady". To add to the confusion and contradiction, the French media this week quoted a flat denial from Lagardère's aides, one of them insisting that since Trierweiler was employed on an indefinite contract, the question of renewal could not have arisen in any case.
Whatever Lagardère's current or previous thoughts on his best-known writer's place in his magazine's editorial team, it has not escaped attention that his first, more damning comments were reportedly made within three months of one of the intemperate outbursts with which Trierweiler has become associated.
She publicly castigated Paris Match for sexism in March after it ran her photograph on its front cover and called her the president's "charming asset". It was not her first or last controversial use of Twitter, the message to her legion of followers reading: "Bravo Paris Match for its sexism ... my thoughts go out to all angry women."
The exasperated tone was underlined, according to French media, in a subsequent message to her boss threatening a boycott: "We won't be doing any more articles with the group."
It was a neat reversal of roles. Lagardère, who numbers Nicolas Sarkozy among close friends, once fired a Paris Match editor for publishing intrusive photographs showing the former president's ex-wife, Cécilia, spending time in New York with her lover, Richard Attias. But this was not the episode that persuaded Trierweiler of the damage to be done on Twitter.
Hollande is said by Elysée sources to have been furious on learning, one month into his presidency and during the June parliamentary elections, that she had rattled off a tweet supporting a rebel socialist candidate standing against Royal in the western constituency of Charente-Maritime. The man she championed, Olivier Falorni, went on to win, despite a desperate campaign by socialist party big guns billed as Saving Soldier Royal.
Trierweiler much later apologised for her "error", saying she had been slow to realise she was no longer an "ordinary citizen". There is also evidence, however, that speaking out for Falorni's - despite Hollande and his party's support for his former partner - was a premeditated gesture.
Entre Deux Feux says Trierweiler was enraged when the president succumbed to Royal's demands that he should publicly endorse her campaign.
"You supported her behind my back without telling me," the authors, citing a witness, quote Trierweiler as telling him. "You will see what I'm capable of."
And months earlier, again according to the book, she had told a friend: "We are submissive until May 6 [the day after the decisive run-off in the presidential elections]. But after that, we'll back Olivier."
What Trierweiler can do to overcome hostility towards her is difficult to imagine. Her treatment by the media may betray signs of professional resentment. She reportedly still collects the salary of a "grand reporter" by Paris Match despite dutifully stepping down from political commentary to restrict herself to culture.
But the public's impression of her is also negative; one poll put the disapproval rate as high as 81 per cent. It seeas pointless to expect attitudes to mellow as to count on her to satisfy what another biographer, Christophe Jakubyszyn, described as France's preference for a "first lady who knows her place, who inaugurates hospitals and visits crèches, like Yvonne de Gaulle".
Trierweiler has fulfilled the first part of her personal post-election manifesto. Smiles in public have replaced the early frostiness. Her dress sense is immaculate. She sought to "represent the image of France" in sympathetic fashion during a visit to Congo.
She has even resolved, to the president's undoubted relief, to count to 10 before sending further tweets. Her Twitter audience has grown from 75,000 to more than 170,000, but the tone of her messages is noticeably milder, the content often mundane.
But Hollande could be forgiven for fearing that another open demonstration of his partner's fiery nature, another embarrassment for him, will never be more than a difference of opinion away.