What are the chances of an emotional abuser healing and the relationship surviving?

Sometimes an abusive relationship changes into a non-abusive one. Sometimes the abusive person has an epiphany and stops the behavior. Often that happens when the other person reaches their breaking point, which may be too late. But if there's still love, there's a chance. The questions are, what are the chances that the healing emotional abuser will stop the behaviors? And can the relationship heal?