What's real? What's not?

   I was diagnosed with schizoaffective disorder about 4 or 5 years ago.  A few months ago that changed to paranoid schizophrenia.  I'm constantly plagued with thoughts and ideas that I can't tell if they're real or not.  I feel I'm being watched and monitored, I have little interest in anything anymore, I feel I'm being talked about and laughed at, I periodically hear things that others do not or don't believe when I tell them; like people laughing at me when no one else is around.  I frequently feel suicidal because I can't make it stop and I don't know what to believe anymore.  My world feels like it's crashing down around me.  The aliens want me dead because I know too much.  I can't take it anymore!