Good luck on deprogramming your step sister, Jivaro. Seriously. I've watched documentaries of guys being deep into and then getting out of the neo-nazi movement. If someone can do that, it is possible for just about anyone. As a side note, I am not surprised there is a Proud Girl group, but I hadn't specifically heard of it previously.
“Extinction is the rule. Survival is the exception.” -- Carl Sagan