All of the above, it depends on the person. There are just some people who are mean, bad sadistic at their very core, but most aren't. I do think a lot of it fear of that association with us will bring out a part of themselves they think is inside them. Since that is it is not logical a lot of it is insecurity. By being mean they are showing there friends and trying to convince themselves their inner fears are BS. For parents of the disabled because of genetics that this is an innate part of them is harder to deny or to conceal from the world. When you add legitimate fear that their child they love will have a rough life and not the life of what is expected, explains the fact that many parental organizations and organizations where parents are clients have become our most fanatical opponents and enemies (enemy is a strong word but not an incorrect one in my view).
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Professionally Identified and joined WP August 26, 2013
DSM 5: Autism Spectrum Disorder, DSM IV: Aspergers Moderate Severity.
“My autism is not a superpower. It also isn’t some kind of god-forsaken, endless fountain of suffering inflicted on my family. It’s just part of who I am as a person”. - Sara Luterman