Do you have any advice for being around a Paranoid Schizo family member?

It seems like your grandmother is both mentally ill and nasty. Sometimes, they go hand in hand. Often, mentally ill people cannot be nice to others, but it seems she is to one son, at least. You don't say how your mother feels about her? You don't say how old you are either. If you are near leaving home and your mom is Ok with her mother as she is, then tolerate the time you have left with them. If your mom is suffering and wants her mother out, I think you should go to a mental facility, expose the situation as you did here, and see what they recommend. Many mentally ill people refuse treatment, have this conspiracy theory you're talking about, but professionals know how to deal with it. She can be forced out of your home and into a facility if she is declared not sane enough to make decisions. Call up the Psychiatry Department of a near-by major university if you don't know where to start or talk to your family doctor.