Conversation in the check-out aisle, two white-haired women each with a cart and a modest number of items. Chatting about nothing, then about Downton Abbey, then about the beloved old movies on the cable. "My husband taped those," one said. "My husband taped them too," the other said. "How long were you married?" "Fifty-six years. And you?" "Fifty-nine. When did you lose your husband?" "Three years ago. And you?" "Three weeks ago." "Oh, my dear," she said, gently placing a hand on the other woman's arm. Knowing enough about what another person might have endured, a deepening...