He went through an incredibly bad drug phase in the early and mid-90s that actually saw him clinically dead for almost two minutes after a drug overdose. Before that, though, he went through a drug-induced psychosis that resulted in some very strange hallucinations. There was a particularly strong one where he held conversations with the Tin Man from The Wizard of Oz.
It was some kind of doll that he had sitting around the apartment. They’d get into all kinds of deep conversations about life, the universe, and everything. But one day, they had a disagreement. The argument escalated to the point where Dave pulled out a handgun and shot him.