I don’t think we can necessarily call all killers psychotic. Antisocials in the broadest of terms, maybe, sociopaths, probably, but they’re not necessarily all losing touch with reality.
In his case, given what we know so far, it does sound rather likely.
Oh man. First time I went to the casino, I brought $40 and left my wallet in the car on purpose as I didn’t trust myself not to go crazy. Good thinking on my end… By the time I was done spending that amount, I was already scheming ways to go and grab my wallet without the people I was there with seeing me go back to the car. The very few times I went back since were with my wife, and she’s great at recognizing and regulating what I call my “stupid brain”, but it really showed me how I shouldn’t be trusted alone with that shit. I can definitely see it becoming a problem if I ever went alone…