"Contempt, disdain" really?  Are we living in an apocalyptic LA or something?  People aren't inherently aggressive, they're understanding and look at us as anyone else, its not the 1800's, they see a sincere person trying and see more honesty than anything else.  They are caring and understanding and simply wish they could help and would love to make you feel comfortable, maybe joke or tease about it to show its nothing and no its not their fault if we take it the wrong way, thats our choice entirely outside their intent.  You seem to take them the wrong way all the same.   I'm going to tell you the truth, you are not mute.  You can stutter through it, your feelings are your own, deal with them or don't but you are not mute.