How do I handle mom's "friends" who tell her she might not have Parkinson's Disease when whe clearly does (Stage 4) and give her false hope?

Yeah, I don't think my aunt wanted to really grasp that my mom is declining. I think friends and relatives just don't want to believe it and resist the truth. Having them tell her good things won't hurt...if and any might be a positive twist to it. I would let them encourage her...it won't hurt at this stage. If it trully bothers you pull them aside and explain your feelings to them, and tell them to turn it down a notch.