Perhaps because we’re so fixated on the dangerous liaisons of current French President Francois Hollande, we were very excited to see Carla Bruni, wife of former French president Nicolas Sarkozy, perform April 19 at Berklee. Alas, Bruni, who became a singer after working for many years as a model, has abruptly — and without explanation — canceled her Boston show. (Tickets can be refunded at the point of purchase.) We’re not sure what the problem is. Bruni was well enough to show up this week at the Schiaparelli Couture fashion show in Paris, looking cool in leather pants and sunglasses. (She did, after all, date Mick Jagger back in the day.) While we wait for the concert to be rescheduled, we’ll console ourselves by reading about Hollande’s titillating love triangle. The French president’s secret affair with actress Julie Gayet was just revealed, and now he’s negotiating with girlfriend Valerie Trierweiler to end their nine-year relationship.