"One of the things research shows us about successful couples is that even when they're talking about problems, they're positive or neutral for 80 percent of the conversation," Don Cole said. "They fill the conversation with statements like 'I appreciate everything you do,' 'I understand where you're coming from.' The smartest thing a man can say to a woman is, 'That makes sense.' The smartest thing a woman can say to a man is, 'This isn't all your fault.' "