Anger From Anxiety/Depression?

I wonder if it's possible that the anger and jealousy I feel might be more from my anxiety and depression, from my a-hole brother in law or has it been a part of me.

I have always had a tendency to want to do the easier of two things. I would get upset when I would be made to do the harder. Or because I think I can't do them. Lately I get so raged inside when someone asks me to do something at work. Usually my brother in law, but sometimes others.

I hate it, I'm nice and I know it. But I've been stuck for so long... What should I do...