I know the feeling myself. I also justify my feelings of anger, whenever I have them.
I suggest looking at your depression as a complex process created by many things.
One of them is being angry towards yourself.
You can then ask yourself why you feel this way.
Another question you can ask is what you tell yourself when you feel this way.
These question can make you understand your situation and your feelings, and you can move more steps forward in unraveling the mystery of depression.
All things I say here are from personal experience. I know how it feels.