You have carried this burden as far and as best as you can. You can't carry it any further for them. I am sorry.
Anger is a big fucking rock. It can be a shield that you hide behind for protection. It can be a weapon when you fling it at someone else. But if you hold onto it for too long, it'll weigh you down, because... it's a big fucking rock. Keep it and use it when it's useful, but be willing to drop it when it holds you back.