[robocat]

I’ll add situational-depression to your list: an ongoing sadness due to being stuck in a bad circumstance (bad relationship, terrible job, etcetera). The defining factor is that once the bad circumstance is “fixed”, the long-term sadness is quickly gone (replaced with ongoing contentment) and symptoms don’t reappear. This is not an academic definition, just a personal observation, although perhaps you have seen the effect happen to others in your life.

I’ve had situational-depression badly enough that I would easily have been diagnosed as clinically depressed (more than one person said so, and if I had gone to a doctor I am sure I would have been given a label and some pills). When the cause was resolved, I immediately switched out of the funk and all symptoms of “depression” were gone. I don’t believe it was correlation, that is I don’t believe depression lifting caused me to fix my bad circumstance: I don’t think I had any influence over the actual date the underlying cause was “fixed”. Chronic clinical depression is not usually fixed in a day.