> wouldn't even be the least bit surprised if I heard they ate a bullet tomorrow

I know it's hard, but I think you have a responsibility to step in when you see things like this.

I've been severely depressed before, and if someone, even if I didn't know them very well, had done something to indicate that they knew what I was going through, it would have helped. Sometimes people who are suicidal are convinced that if they did eat a bullet tomorrow, no one would care.