They just don't seem to care that we've been hurt. And no matter how much we hold onto our anger, we continue to get hurt over and over again. Our anger never seems to protect us. And the reason for this is that pain can never produce anything but pain. It can never produce peace or pleasure or resolution.
Anger can never produce love.
Only love can produce love. This is an immutable law. Like a law of physics. So we have to find a way to let go of our anger. Rabbi Harold Kushner tells the story of a divorcee who came to see him furious after he had delivered a sermon about forgiveness.