what is it with all these young kids dying? wasn't there a post like only a few days ago about a guy losing his cofounder to a car accident. how did he die, if you don't mind me asking?
No clue what the factors are in this particular case beyond what's in this thread but I've seen people literally break because of the strain a start-up put on their lives.
Working past what your body can normally do and taking on mental burdens past what you could cope with under normal circumstances (huge responsibilities) is not going to be without its consequences.
Again no idea how much of that was a factor here, but I really think that those that get into the game should be very much aware of the pressure and should be able to somehow get rid of that and always remember that even though your start-up is important it is never more important than you and your health.
Don't push it too far.