Or he could just be paranoid. I know I am a bit. I still wouldn't say psychotic. He isn't seeing ****, which is losing touch with reality (such as Harry is). I know that seeing **** isn't the only means of psychosis, but to me he's just paranoid. Spiderman did screw up his life with the story. He has an unhealthy obsession (as do most people, just not with another person) and is in denial. Not psychotic.
That's just my interp though.
And, in case you guys forgot, Topher has been in several movies. Including Traffic... though I think he was only the freaking out boyfriend of the girl who overdosed. Not quite sure. I haven't seen that movie in a long time. And a lot of actors, such as THC, were in tons of movies before being noticed (THC was in roughly 22 movies before being noticed) while others hit spot on in their first acting job.
Being caught in one role is death to the actor (ie Mark Hamill - when was the last time you saw him in something other than a Sci Fi related movie)... which is why I'm glad that Topher is actually getting a serious role for once.