Please speak for your co-worker. This is discrimatory behavior, perhaps abuse. Can you report this anonymously? Anyway, do say something or else you're condoning the bias too. If you were treated in this way, wouldn't you need/want one to stand up for you? I do not mean to be harsh with you (I know this is not your fault, of course), but please do not let another Autie be hurt by this bigotry. I assure you, your autistic co-worker feels the hurt acutely. Watch out for each other. No one else will.
Of course, be respectful to your boss - you do not need to lose your job, or your co-worker's, but do act on this behavior! Can you report this to the ADA or Human Rights Commission, at least? Just a suggestion. In the long run, you'll be doing the right thing. Please consider.
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The ones who say “You can’t” and “You won’t” are probably the ones scared that you will. - Unknown