How do you handle yourself with people that you do not like?

I agree with you. Not only do I feel discomfort, but I am also bad at pretending doing something that goes against my heart. I can't even be civil. I get nasty with words (sarcastic) but I try to avoid it so instead, i totally ignore them. I am usually a warm person and everybody appreciate my presence because I try to spread optimism and friendliness. So really, I feel sorry for the person that I do not like...