Sans the cocaine habit, and the staggering productivity levels, the second example is an otherwise uncanny match for how I eventually left my last job.

Started off strong, got ahead of schedule, had a mental breakdown, accomplished exactly nothing for about a month, and then quit (to avoid being fired).

Let me guess, you do all overall design work, train staff, stay late. Then someone else gets the credit, because his best friends with the manager?

That was my last mental breakdown.