But loneliness in marriage can be bitter. Caroline, now 47 and a successful writer, was married for 12 years to a man who, though never cruel, felt increasingly absent. “He was very gregarious,” she says, “always the life and soul of the party, but really very insecure. When we were alone, he would disappear into himself. He didn’t really either talk or listen. There was nothing I could put my finger on, but in a way that was the trouble: there was nothing.”