I'm just trying to make a distinction between the mental and physical aspects of a situation- and there may not be a difference.

For true clinical depression, there isn't a difference. That's what we've been trying to tell you.

The human brain is like a very complicated chemical computer. It can malfunction just like any other part of the human body. If the delicate chemical balances that govern the human brain are broken, you get conditions like depression, addiction, and other mental illnesses. These are illnesses just like Alzheimers or Rabies or the common cold, they simply have different causes. As I quoted before, you can't "will them away", they must be treated.