I am amazed at Ozon's insight into loss. When death is so sudden there can be the illusion of life continuing, particularly when a couple have grown together for so many years. We are led to see everything from Marie's point of view to the point that even her best friend, Amanda, seems unsympathetic. When Marie does attempt to move away from Jean's memory, the new lover, after only one night, is already volunteering to help her with her "problem". The brief scene with mother-in-law is superb. The allusions to Virgina Woolf are also key to understanding.
For me, it is the sympathy given by Ozon to the character of Marie, the one who has to cope with loss, which gives this film such power. Without a hint of indulgence, we see a strong character attempting to survive an experience which has shattered her life.