Prison.
It's a barrier to so many things for me - getting a job, driving, living on my own, speaking, having anything resembling a social life, learning anything actually useful (because I spend too much time on my obsessions instead, which aren't even remotely useful)... actually, it would probably be much shorter to list the things it doesn't negatively affect for me. I'm jealous of people for whom autism can be reasonably seen as not being a disability - for me, it absolutely is. It really does feel like I'm imprisoned by it.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"