I don't think this is psychosis. it's just conspiracy theory, in an age where there is so much to theorize about, what with Prism,. and the rise of "The Internet of Everything". Most Americans still think that JFK was murdered by a huge conspiracy. I believed this myself for most of my life. My first girlfriend was an Anthropology Grad student who believed that the government had framed Sid Vicious. And now our computers and even our TVs are really watching us. It's almost a natural progression to imagine being stalked and followed.
The idea that you're being watched these days? Not crazy.
The idea that it's a global conspiracy run by the illuminati and lizard people led by a clone of an Egyptian pharaoh and they're after YOU, PERSONALLY and they must be EXPOSED? Totally batshit.