What a whirl. Man falls in love with married woman; woman leaves husband for him; woman falls out of love with him, takes a new lover, leaving for good. It’s all so French. This bed-hopping routine, all of which took place in Paris, could be a Louis Malle romance starring Gérard Depardieu and Emmanuelle Béart. But this drama is real, and it stars none other than the president of France, Nicolas Sarkozy, and his pulchritudinous partner, Cécilia, the first lady of the republic.

After almost 20 years together, Cécilia has decided to leave her comfortable life in the Elysée Palace. Setting a historical precedent, the Sarkozys have separated while he is still in office, and the French public are lapping it up. Yes, it’s sad and private, but what a saga. An opinion poll by the newspaper Le Journal du Dimanche said that 89% of those canvassed believed the divorce was a private affair, yet magazines that featured the break-up on their covers have seen their sales soar.

Now she is no longer part of the first family, there has been an abrupt end to deference: reporters are delighting in revealing that Cécilia was nicknamed “the Spectre” during the presidential campaign because she was so rarely seen. Others reveal her as moody, “mad” and prone to throwing tantrums. She is said to have been attention-seeking, insisting on Sarkozy bunking off when he was interior minister to go for a stroll with her; and she has been criticised for embarrassing her husband during talks in 2005 with the Ukrainian vice-premier in Kiev by studying her nails in utter boredom.

She is also said to have blacklisted several close aides of Sarkozy, including his friend of 30 years Brice Hortefeux, the immigration minister. Hortefeux has yet to dine at the presidential palace. Hortefeux and others snubbed by her have set up the SVC club – the Society of Victims of Cécilia. Perhaps they are behind those comparing her to Cruella de Vil, the puppy murderer from One Hundred and One Dalmatians.

Anyone who has followed the on-off Nicolas and Cécilia romance knows their relationship has never been smooth. Cécilia, a former model for the fashion house Schiaparelli and law student, left her first husband Jacques Martin, a television personality, for Sarkozy in 1988. They married eight years later in 1996 and had a son, Louis, now 10. From the start she was never comfortable standing by her man. Although she worked as his adviser and publicist she confided later that she felt she had “put a pillow over part of my life”.

In the spring of 2005 she fell in love with Richard Attias, an advertising executive, and left to live with him in New York. Sarkozy started a relationship with a journalist on the newspaper Le Figaro – they were seen buying a washing machine and a fridge together – but he never stopped wooing Cécilia and persuaded her to return the following year.

Much was made of this rapprochement. Was it for real or was it merely for the presidential race? Although the couple made high-profile trips to Venice and Morocco, there was strain beneath the surface. She failed to vote in the May presidential election, only agreeing to join him for his victory celebration, her hair untidy and wearing no make-up, after her daughters and a host of friends persuaded her.

In June she abandoned the G8 summit of leading nations in Heiligen-damm in Germany to return to Paris, officially to celebrate her daughter’s birthday. This summer, on holiday at Wolfeboro in America, she pulled out of a meeting with the Bush family at short notice, officially suffering from a sore throat.

In July, however, she pulled off a notable victory. Making two trips to Libya, she helped negotiate the release of five Bulgarian nurses and a Palestinian doctor who had been unjustly accused of infecting more than 400 children with the Aids virus. She obviously has diplomatic powers coupled with a keen intelligence – which makes her disappearance from the Elysée all the more remarkable.

Much to her exhusband’s dismay, she gave an interview to a regional newspaper, L’Est Républicain, on the day the divorce was announced. Here, for the first time, Cécilia Sarkozy explains why she ended her marriage:

Why speak out now?

I think I have to explain why I no longer want to play the role – if there is such a role – of France’s first lady, the reasons why I’ve asked for a divorce and why I want to withdraw from public life.

Those two key elements: your withdrawal from public life and your divorce. Which is the most important for you? Does one explain the other?

You can’t separate the two. Two years ago something happened to me. In 2005 I met someone, I fell in love, I left – perhaps a bit hastily given the media attention I was still subject to at the time. I wanted to try to behave correctly and to come back to try to rebuild something, to try to follow the principles I was brought up with. That’s the reason why everything happened quickly without my being able to manage things completely.

I haven’t spoken for two years. I have to tell you that this public life doesn’t suit me, it doesn’t correspond to what I am deep down. I’m someone who likes the shadows, serenity, tranquillity.

I had a husband who was a public figure, I always knew that, I was at his side for 20 years. This struggle led to a specific place [the Elysée], somewhere where I think he is wonderful because he is a man capable of doing a great deal for France and the French. But as far as I’m concerned, I don’t think that’s my place. It is no longer my place. And as journalists and commentators have often said, the French elected a man and not a couple.

For you, the election of Nicolas Sarkozy to the Elysée – had you, in a way, accomplished a mission?

No. You’re mixing up private life and public life. But it’s true that when you marry a political figure, private life and public life are one and the same. That’s where the problems start.

I didn’t accomplish a mission, it was a common struggle. I’m a woman who commits herself, I need to do so. I need to prove, especially to myself more than to others, that I’m capable of doing things.

So, for 20 years it was a struggle, but there were also interesting, fascinating moments because politics is fascinating. For my husband, it’s like a violinist to whom you give a Stradi-varius, he suddenly has the opportunity to practise his art. For me, it’s not at all the same thing: I worked at his side, but I wasn’t elected and I didn’t want to be elected. That’s one of the reasons why it was not my place.

What led you to take the decision you have?

What happened to me has happened to millions of people: one day, you no longer have your place in the couple. The couple is no longer the essential thing in your life, it doesn’t work any more. The reasons can’t be explained, it happens to lots of people. It happened to us.

We tried to reconstruct, to rebuild things, to put the family before the rest, to make it the priority, but it wasn’t possible. We tried everything, I tried everything. It simply wasn’t possible any more.

Does this explain your absences during various official ceremonies and during trips you were expected to take part in?

A crisis doesn’t arrive from one day to the next. I went back home a year ago: for a year, I tried to commit myself professionally, personally, but it didn’t work every day. During the G8, I preferred to leave because my place wasn’t there any more.

I think people can understand that there are times in your life when you’re in less good shape than in others, these crises can happen to everyone. So I preferred not to show myself, to protect myself.

One of the worst aspects of my position is this obligation to explain the fact that I need to live calmly, hidden.

At the same time, the fact that you don’t appear where you are expected to has fuelled what people call “the Cécilia enigma” and “the Cécilia mystery”.

There is no enigma, no mystery, there’s only a couple going through a crisis who tried to overcome it but didn’t succeed.

What’s more, I suffer from the fact that my private life is explained, dissected with shocking things published; anyone would suffer from that. People who say the opposite aren’t telling the truth; there’s no shell solid enough to protect yourself from that . . . I’m going to try now to live discreetly and in the shadows, as I like to do.

But the freeing of the Bulgarian nurses in Libya put you back in the spotlight.

I did this without thinking of the media impact. I was talking to Claude Guéant, the secretary-general of the Elysée, he told me: “I’m going to Libya.” I felt that I could help.

I felt I could make a contribution even if the situation had been blocked for a very long time. I told him: “I’m coming with you!” In the plane, I tried to understand the case. I dedicated all my energy to it. I spent 50 hours discussing, talking, negotiating with many people to try to obtain the only thing that interested me: to get these women and this man out. I had given them my word, I had to keep my word and I felt I could do it.

It needed all one’s strength of will, all one’s heart, all one’s anger. I succeeded and I’m very pleased. I didn’t expect anything in return and I don’t understand the controversy because my only motivation was to get out these people who had suffered atrociously, to just get them out of prison.

I didn’t think of the media impact, or of the explanations people would ask me for, or of anything whatsoever. I just did it with a humanitarian objective . . . I did what had to be done with the help of Claude Guéant and Boris Boyon, the diplomatic adviser, who were with me and who ensured everything went for the best.

Did the mission make you want to keep working in the humanitarian field?

I think I have much strength of will to do so, a lot of tenacity and of luck. I don’t know if all this will happen again. It’s not only with the Bulgarian nurses, I’ve always committed myself to offering a helping hand. I’ll continue to do it, whether it’s in the media limelight or not.

In what way? Do you want to create a foundation?

No. For the time being, I have no plans. I want to do lots of things and I feel I can help others. That’s always been in my nature, I’ve always been reaching out to others.

How did you feel when you learnt that your husband was to be president of France after all those years of struggle?

I was proud! I was proud because it’s the work of a lifetime. It took sacrifice, many sacrifices to obtain it. However, I think he is part of that race of men who put their career and their life at the service of the state and don’t expect anything in return. I was proud and happy for him.

Many things have been said about your role at his side. You were an adviser, you had influence, you were part of making strategic decisions. It was even said certain ministers owed their jobs to you.

Nicolas has absolutely no need for that kind of advice. I’ve always tried to be a safeguard for him because I’ve got a point of view that is outside [his circle] and I’ve always lived a life which is a bit outside and parallel to political life. I look at things with a fresh eye.

However, as far as nominations and decisions go, I keep the door of my office closed. I’ve never wanted to interfere in any way. But I think an impartial piece of advice coming from outside, given that I didn’t expect anything in return, was by definition a good piece of advice.

What are you going to do now? I’m going to concentrate on my family. I don’t want to live constrained by my past. I don’t like to live among ruins. A page turns, it’s difficult, but I never regret my decisions. Even when I was a child, when I finished a drawing I’d turn the page and start another one. Well here, I’ve picked up my brushes to paint a new story.

Cécilia Sarkozy was talking to Yves Derai for L’Est Républicain (Distributed by The New York Times Syndicate)

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