Fabius cited French writer Francois-Rene de Chateaubriand to say Macron was "a man of the times," adding, "even in your marriage".
Dressed in a powder blue above-the-knee Louis Vuitton dress and a matching jacket with golden buttons - designed for her by Nicolas Ghesquiere - Brigitte looked on.
In one sense, the French election was a choice between two very different kinds of marriage - while it was the nationalist Marine Le Pen that Macron faced in the runoff, his main challenger for the votes of the mainstream majority was the catholic conservative Francois Fillon.
Fillon's wife Penelope was paid a public salary for helping her husband since the early 1980s, but allegedly did very little actual work. Brigitte has been an unpaid adviser to Macron throughout his campaign and now takes on an official role like the first lady in the US, though she still doesn't get a salary.
"There's a deep desire for a renewal of the political class and a wish to break free of old social norms and ancient codes of conduct," said Mariette Sineau, a political scientist and sociologist at Sciences Po institute in Paris. "French society is much more liberal than people outside the country or even in the media realise."
Brigitte, 64, played a key role as her husband vaulted from junior minister to president in less than a year, advising him on speeches and helping to shape his agenda. In fact, she's been a central figure since they met as teacher and 15-year-old student at a high school in northern France.
His openness about that relationship has become a key part of the new president's political identity that he uses to reach out to different groups of voters. In an April session of interviews with Snapchat one user said he'd fallen in love with his law professor and asked Macron for advice.
"First find out if it's shared," Macron chuckled. "If so, go ahead! No Taboo!"
In a C8 television programme filmed with school children in a classroom in March and aired on Sunday in full, Macron is candid. Explaining Shakespeare's Romeo and Juliet to the group, he says, "It ends badly, and that's sad. But love is stronger than the rules of men."
He goes on to talk about his own situation, saying "There are many different kinds of families... What matters is that it's a project of love."
On International Women's Day in March he said, "There is no less love in our family" just because it's unusual. In a February interview with the gay monthly magazine Tetu, he said speculation about him and his partner was an "odious" reflection of the fact that politics is still very "male".
The Macrons' image as a tight-knit couple has been crafted with the help of Michele Marchand, the head of Bestimage, one of France's most powerful paparazzi agencies.
Marchand flooded France's weekly magazines with iconic images after his election victory. One picture in Paris-Match of Macron writing his victory speech as his wife's grandchildren play around his desk in this week's magazine recalled a similar shot of former US President John F. Kennnedy.
Yet the age gap, and the origins of their relationship, has provoked some nastier chatter.
Charlie Hebdo, the satirical weekly known for its biting cartoons, featured a pregnant Brigitte on its cover this week, saying "He's Going to Work Miracles!" The Financial Times on May 8 described her as an "Essex Girl" in a piece that also used the French word "cagole," pejorative slang for an overdressed and vulgar blonde. Delve little deeper into social media, and there's much worse.
The sniping prompted Elle Magazine, the weekly arbiter of fashion and social trends for French women, to publish a defence of Brigitte before May 7's final vote: "Brigitte Macron's Age: How Much Longer Are We Going to 'Laugh' About It?"
Editor-in-chief Adele Breau said the comments about the couple were "ultra-misogynistic" and the suggestion that marrying an older woman meant the candidate must secretly be gay were "homophobic". The article went viral with as many as 700,000 people reading it on Facebook and over 300,000 views on the magazine's website, a record.
The challenge for the Elysee is to ensure that the Macron marriage doesn't become a political liability, in a country that has at times been uncomfortable with personality politics. A May 10 poll by YouGov shows 68 per cent of French people are opposed to the first lady having a formal status.
"US public opinion is much more conservative in terms of values, but it's more accepting of people's personal lives," Sineau said. "In France, it's the reverse. Macron mustn't overplay his relationship or there will be a backlash."
- Bloomberg
