Some people believe what they *want" or "have" to believe. No amount of facts can change them. Conspiricys have an answer to any fact. It's tough when its your loved ones. People do change sometimes. I have seen close friends over the course of a decade change their politics. It is a slow process.
My bumper sticker still reads, "REMEMBER 9-11, GET THE BASTARDS." And another one reads, "LET'S ROLL!" both with the American flag waving.