I cannot count the number of times that I have heard... Why are you looking so mean? In my mind I have a blank expression. Because I wasn't joining in the conversation people used how THEY read my facial expression because I wasn't saying anything. Nine times out of ten they got it wrong.
I learned a proverb that said : “Counsel in the heart of a man is as deep waters, but the man of discernment is one that will draw it up.” (Proverbs 20:5) Imagine how hard it would be to get water out of a deep well that's like 75 feet deep. It takes work! People need to understand that sometimes they have to draw a person out. By showing interest, asking tactful questions, they would be letting down their bucket into a deep well...making an effort to talk to someone who struggles with SA. I have appreciated so much when a person has asked me a tactful question like "do you feel that way too?" to help me get started with saying something in a conversation. That is so much better than "You can talk you know."
I've been misunderstood as being rude and unfriendly because of being too quiet. Also gave the impression of being aggressive and having a bad attitude. The bad way I came across got me asked to leave a recent job volunteering.