I don't know about rage, specifically, but I think it is a coping mechanism for an undesirable state of affairs. Your mind numbs itself and accepts that things suck to try and keep your body alive. You distance yourself from others, stop doing hobbies, drop out of school, etc., as your mind distances yourself from things until the actual problem is left behind. Problem is, the "actual problem" for people in the west is the way we live. We're controlled by foreign (to the self) powers we likely won't ever meet or influence. We live increasingly in dehumanized pods (i.e., isolated homes and apartments where we don't grow a close society of people.) The mind knows this and recoils. So, drugs may dampen the dampening feeling you get from depression but it doesn't solve the fact that we're increasingly isolated, fat, shamed, stuck working indoors away from the sun, have little freedom, and know that generations to follow us will be in the same hell.