When I was in nursing school one of my instructors found out that I was from a fundamentalist community. This was the 2nd week of a 2 year long program where I would be with the same people everyday.  In front of at least 10 people in my cohort, she announced very loudly that she knew exactly who I was (this because we found a common acquaintance), and then proceeded to tell everyone that I was a "polygamist".

She said "oh I have no problem with your kind, as long as they aren't forcing 13 year olds to get married," perpetuating a false stereotype at my expense in front of my peers.  I was speechless and my face turned red with embarrassment and anger.  She said "red suits you well" and walked away before I could say anything or stand up for myself.  I was afraid to stand up for myself and report this behavior because the staff had scared us so much that we were replaceable in the program, and that we were lucky to be there, and I didn't want to risk losing my place in the program.