If I sense people are treating me differently, or I'm told that people are talking about me behind my back, I will tell them to give me a break, because I'm autistic. Normally, it makes people feel kind of guilty, and they seem sort of embarrassed, and often apologetic. Sometimes they will then completely ignore me, but I prefer that to actually being talked about or picked on.
My friends that are know but don't really understand tend to be quite worried if I seem in a distant sort of state, and don't like to leave me alone, because they know I have a history of depression and self-harm, so they often take me to each of my classes, and sometimes treat my like I'm a lot younger than I am. Sometimes though, I know that's what I need: the sort of firm instructions that you'd give a youg child.
Most people are OK with it though, they tend to nod and just go 'OK,' when they find out, and it generally doesn't bother them. I try to teach people as much about autism and Asperger's as I can, and I think being open helps stop misconceptions a lot of the time.
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'I may not amount to much, but at least I am unique.' ~ Jean-Jacques Rousseau
'I sometimes go to my own little world, but that's okay, they know me there.' ~ Joel Hodgson