Head injuries ==> depression ==> suicide. That's my bet, anyway. I read he had a pretty severe traffic accident with a serious head injury, and who knows how many concussions after that during a long BMX-career.
Besides, if anything, "guys who have it all" are overrepresented in suicides as far as I can see.
Besides, if anything, "guys who have it all" are overrepresented in suicides as far as I can see.