The question in the title of this Guy de Maupassant story could refer to two things: the blissful year the protagonist shared with his lover, or the vision he had while visiting her grave. Similarly, the feelings of emptiness and loss he experiences could be because of two things: the unexpected death of his lover, or what he learned/dreamed about her death in the cemetery. Themes include blind love (idolization blurring reality), infidelity and betrayal (perhaps on two levels if, as the first priest suggested, the woman was his mistress), obsessive grief, dreams/the supernatural.