Speaking as someone who has actually been suicidal, it does seem pretty clear that he was depressed. From his blog posts it seems that he typically had a lot of

Speaking as someone who has actually been suicidal, it does seem pretty clear that he was depressed. From his blog posts it seems that he typically had a lot of stress-related health symptoms over the years, including depression. It seems that he simply tried to do too much, got burned out as a result, and couldn't/wouldn't talk about it to anyone. Not all depression fits nicely into the 'clinical depression' pigeonhole.