Children, mine and others, don't do this don't. If you meet someone who just puts you down: walk away. I woke up feeling I'd wasted a good part of the evening hurting myself, gaining exactly nothing for it but a lowered self-esteem. There are enough nice, sympathetic people out there for you to spend time with instead of wasting it on people who think you're not up to their own standard.
Ps. The odd thing is that I didn't even dislike him, just disliked his ways. Felt like elementary school all over again.