Some of the people who have hurt me worst are very hard to get mad at. You say anything to them about what they've done wrong, and they collapse inward into violent paroxysms of guilt.
This is difficult. It feels like they can't or won't face the consequences of their actions. . . but I still have to. Some part of me really wants to hurt them, but yelling at them to try and make them understand would be like kicking a puppy; monstrous, horrifying, and not at all useful. In the slightest. To anyone.
I think anger is useful. It seems there are two good responses to it. If anger is telling you about something that ought to be changed, change it if you can. That's what anger is for, to fuel battles, to keep you awake and strong and make you remember what you fight for.
If it is impossible to change--there is only to mourn what you've lost.