How the French View Life as a Couple PARIS - It may not be as juicy as Closer, the weekly gossip magazine that broke the story about President François Hollande's love affair with the actress Julie Gayet. And unlike the mini-series at the Élysée Palace, the report this month on France's overall married state was a snapshot in time, a year-end summary of the number of French couples who opted for marriage and those who chose the looser civil union known as the PACS. In 2012, the last year with statistics for both kinds of partnerships, the ratio was three marriages for every two PACS (245,930 and 160,200 respectively). In 2013, the number of marriages - 300,000 in 2000 - dropped to 231,000: the figure would have been lower without the 7,000 same-sex marriages registered under a much-contested law that took effect last May. The French statistical agency Insee has yet to publish the number of PACS in 2013, but the trend remains clear: Fewer French couples (except same-sex couples) are getting married every year. That includes the president himself, who isn't married to Valérie Trierweiller, the scorned woman in the current affair, and wasn't married to Ségolène Royal, his longtime partner and the mother of his four children. As Mr. Hollande keeps insisting, these are personal choices that don't concern anyone else. To some extent, that's true: In 2012, French voters paid little attention to the Socialist candidate's unmarried status, and didn't blink when Ms. Trierweiller moved into the Élysée Palace as the president's "companion." The president and his first lady didn't even opt for a PACS. But even after Mr. Hollande announced on Saturday that he had put an end to his relationship with Ms. Trierweiller, the status of a presidential companion remained a subject of considerable fascination. No matter how much the mainstream media tiptoed around Mr. Hollande's domestic dilemma, ever mindful of France's strict privacy laws, it is clear that the French are following the affair closely (even as they tell pollsters it's none of their business.) So what does Mr. Hollande's unmarried state have to do with this lingering fascination? A lot, according to François de Singly, a sociology professor who in an opinion piece in the newspaper Le Monde wrote that living in "concubinage" (the French word is a lot sexier than the English "cohabiting union") is a "legitimate choice, but it has consequences." One institutional function of marriage, he argued, is to put a "public" face on a private life, one that can provide "public" refuge from the turbulence of adultery. Other French presidents have had mistresses - some more than one - but their affairs (not publicized but well known) didn't threaten their wives" role as France's first lady. In contrast, concubinage, which has no status, draws its only legitimacy from the love and affection shared by the couple. When that's gone, there is nothing left, which is why Ms. Trierweiler's status was so precarious. If Ms. Gayet is Mr. Hollande's mistress, then what did that make Ms. Trierweiler? According to Mr. de Singly, the live-in-lover model "doesn't tolerate a mistress." That's the theory. Reality is another matter; couples stray, and split or stay together, regardless of their union. Since 2004, the number of divorces in France has oscillated around 130,000, even as the number of marriages decreases. In contrast, only 49,000 civil unions were dissolved in 2012, of which interestingly, 40 percent moved on to the stronger bonds of marriage. In other words, it's not that French couples are reluctant to commit. In fact, the PACS "is often compared to an engagement," noted Christophe Giraud, a Paris-based sociologist. In his view, the issue raised by Mr. Hollande's domestic mess is not which vow he broke, but the fact of his betrayal. "What is shocking is not so much the non-marriage, non-PACS situation as the double life François Hollande seems to have been leading," Mr. Giraud wrote in an email. The French more or less accept the various forms of private life, but they are shocked by the cheating, and the lies within the relationship.