I feel this is an overly simplistic view of depression. I imagine there's a thousand reasons for a state like depression to emerge — some, but not all of them

I feel this is an overly simplistic view of depression. I imagine there's a thousand reasons for a state like depression to emerge — some, but not all of them external. I think the Venn diagram of people with depression and people whose "lives suck for whatever reason" is not a single circle.