"People in breakups often react badly, expressing their anger and sorrow in an attack-style form of communication," Caspersen says. "Be prepared for this and focus your attention on what the other person is really trying to say, even if they are saying it very badly. Let them know that you heard them, even when you disagree."
O'Malley agrees. "Let them have their reaction," he says. "Be willing to sit there and take it. They will call you names. Don't call them irrational or tell them to calm down. Take it quietly."
The one exception? If he or she becomes violent. Then, O'Malley says, "get the hell out."