Meh, those birth parents of mine are indeed insane. I'm not! I thank God for sanity.
Did they do their best? I don't know. I really don't care. I don't talk to or even, usually, about the drunk bio-father. I have a new dad, and he's perfectly great. Mom? Still thinks like a sick person. I learned boundaries, though, and I'm fine.
What's so bad about getting angry? I think it's ok not to like something that's bad for you.
I think as long as it's not all consuming anger, and you're able to present wonderful things into the world, it's really ok to be angry. Sometimes.