Street, so sorry to hear of the loss of these people you
knew.
Depression is no joke. I have lost more friends and people I know than I can count on both hands. All but one had more money than they could spend, most had a great family and friends. Two were doctors, many more were farmers and successful business people. Some diagnosed with incurable disease. I don't know one that took their life because they were broke or because of financial failure. Most were loaded. I can count 11 men and only one woman.
A couple years ago I was diagnosed with a physical disease (PMR). Hurts like hell. The first thing the doctor did was get me checked out with a phycological test. I told him "Doc, I hurt all over but my head is OK" He explained to me that certain physical diseases (PMR) send chemicals to your brain that you're dying. This doctor is a farm kid like me. He said "did you ever have a dog that went out to the woods when he knew he was dying" I said, "sure, everybody has". He said that the body sends these signals to the brain. "Same thing you have." It made me think again.
Mental illness is the same as physical illness. Respect it and treat it.
I am much more aware of it now and will do my best to intervene, even if I'm not wanted.