[Buttons12]

...many aspects of clinical depression and many cases have nothing to do with life events at all.

That's really amazing when you think about it. An overall, pervasive emotional atmosphere unaffected by life events, and, I take it, not affecting them either. Or is there a sort of membrane through which things flow one way only? Curiouser and curiouser, cried Alice.

[Chickensoup]

https://www.psycom.net/depression/major-depressive-disorder/dsm-5-depression-criteria

this is a good laymen’s definition