I think what you said about anger being rooted in entitlement applies to the whole human race. One of the things I've learned is that if I want to have a peaceful spirit, I have to have an attitude of yielding my rights. And it really works. When you realize you don't have any "rights" and you're not entitled to any expectations, there's a lot less stuff out there that can ruffle your feathers.
Every now and then, I get angry out of proportion to what was done to me. When that happens, I take it as a sign that an inner wound, probably from my childhood, has been re-opened. I have a ritual I go through for healing from old wounds which includes forgiveness of the perpetrator/s of the original wound, which is the only true way to get it healed for good.
Perhaps that's different from what the psychologists mean about turning your anger inward because it's a well-known saying in those circles that, "Depression is anger turned inward". I know when I get depressed it's because I'm angry and usually don't even know it. I'm not one to be "in touch with my feelings".
It seems that the way I internalize my anger is different from the way that you do it. Yours seems to be more healthy. My way is self-destructive.