Sous le sable / Under the Sand (2000)

Marie, a professor of English literature in a Paris university, has been happily married to Jean for 25 years, although they have no children. During their summer vacations in the southwest of France, Jean leaves Marie sunbathing on the beach and goes to swim in the sea. When Marie turns back, she cannot find Jean. Has he left her? commited suicide? drowned? With no clue and no body to mourn over, Marie acts as her husband was still alive.

Imdb