Why do i care what people say about me?

they can ruin my day with a single word...

I care, too. It's just human nature to internalize others' comments. I guess all you can really do is to try and build up your own self esteem by listing all of your great qualities and also accept the fact that nobody is perfect, you included. So what if somebody makes a comment about one of your shortcomings? We all have them. :) Good luck and try to keep your chin up!