The first wife of President Nicolas Sarkozy has emerged from self-imposed seclusion to declare that she has forgiven him for the infidelity that led to their divorce but has not forgotten her betrayal by her friend Cécilia Ciganer-Albéniz, who went on to marry him.

In an interview for a book on Sarkozy’s relationships with women, Marie-Dominique Culioli, 53, who was at his side when he launched his political career, condemned Cécilia in terms that shed an unflattering light on the president’s private life.

“Cécilia was my best friend. She did everything she could to win my friendship to get close to my husband,” Marie-Dominique told Candice Nédélec, co-author of Sarkozy and the Women, to be published this week.

Cécilia, 50, was divorced last year from Sarkozy, who then married Carla Bruni, 40, the model and singer.

Marie-Dominique, the daughter of a chemist from southern Corsica, met Sarkozy, then a newly elected councillor in the smart Paris suburb of Neuilly, while still a student at the Sorbonne in 1980.

A devout Catholic, she saw Sarkozy as “a spiritual person, very modest at heart”. At the time, she said, he had none of the fondness for Ray-Bans and Rolexes that earned him the nickname of President Bling-Bling.

She helped Sarkozy to build support in what was then known as the “Corsican faction” of the Gaullist party. Marie-Dominique took a job as an Italian teacher and they settled in a flat above the home of Sarkozy’s mother, holidaying at her family’s seaside villa in Corsica.

Two years after their marriage, Sarkozy presided as mayor of Neuilly at the wedding of Cécilia and Jacques Martin, a television personality. Unbeknown to Marie-Dominique, he fell in love with Cécilia. The two women became friends, raised their children together and attended dinners with their spouses at the best Paris restaurants.

Marie-Dominique discovered that Sarkozy was having an affair in 1988 when the two couples went skiing in the Alpine resort of Megève. “Marie drummed on the door of Cécilia’s room. There was a sound inside. [She saw] Nicolas’s footsteps in the snow,” the authors write.

Marie-Dominique did not want a divorce and Sarkozy “went backwards and forwards between the two women”, according to the book. Marie-Dominique had borne Sarkozy two sons, Pierre in 1985 and Jean the following year, whom she told: “One day your father will be president of the republic.”

Her anguish was compounded by breast cancer and it took eight years to agree a divorce settlement. Sarkozy finally married Cécilia in 1996.

The last time Marie-Dominique appeared at a political rally with Sarkozy was in 1989. She has long since pardoned him for the break-up of their marriage. “Nicolas is the father of my children,” she said. “Many men have made mistakes and have fallen for temptation.”

However, she refuses to let bygones be bygones as far as Cécilia is concerned. “He was led astray by that girl. It’s that girl who made him fall for her,” she said. According to Nédélec: “She is still angry at Cécilia. She blames her for all the things Sarkozy is criticised for today – his love of luxury, his ‘bling-bling’ nature.”

Since the divorce, Marie-Dominique has had almost no contact with Sarkozy. She has found comfort by teaching religion and working for charity. In May 2007, at the height of the campaign that was to propel Sarkozy to the Elysée Palace, she sought refuge from all the publicity in her Corsican village.

Shortly after the results were known, she telephoned the new leader. “You know, I voted for you,” she told him.

“I know, that’s nice of you,” Sarkozy replied.

She was furious to see Cécilia with the children of both marriages at the inauguration. “My children have never been raised with hers,” she protested.

She now works at the Neuilly branch of Sarkozy’s party, helping her son Jean, a newly elected councillor, and calling herself Madame Sarkozy.

Sarkozy has only himself to blame for the intrusive books about his private life, according to French commentators.

“It’s the direct result of Sarkozy giving too much exposure to his relationships with Cécilia and then with Carla,” said Stéphane Rozes, head of the CSA polling institute. “The French are interested in a candidate’s private life during an election, but once he’s in office that’s it.”

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