Why is this guy trying to hurt my self esteem so badly, has no heart at all!?

He's probably intimidated/self conscious about you and tries to belittle you in his own attempt to either make you feel bad to make himself feel better or so you won't find anyone. Just keep your self-esteem up and it'll drive him crazy, he's either a prick for treating you that way out of his personal enjoyment or just really intimidated by your looks or personality.