You're right. This is actually spot on.

I'm not saying it would definitely happen to him, but what's specific to him is that she is on his mind all the time.

If you're thinking about someone or something constantly while off your tits, there is the possibility that you'll start to make up theories & shit in your head of what's going on, especially if you are taking strong or high amounts of amphetamine with hallucinogenic effects.

Again, yes that's my personal experience but I'm only pointing out that it's a possibility, no matter how big or small.