Why every time that I say I am Iranian (middle eastern) people start to act differently?

I can understand what you mean,Some of my so called friends are also racist as well.This one time I was having a god time with a group of 5 and it went well for like 5 months until they found out I was anarab.After that they started to discriminate me and insult me afterwards.Yes I know it's really racist but what are you gonna do about it?On top of that they'd call you and me terrorists but whos the one with more bombs?