Hatred and Anger

Have you ever disliked someone that you don't really know so much that you can't even pretend to act normally around them?
I don't even know why I hated this person. Maybe because I somehow feels that this person, namely A, has taken someone that I care, let's pretend it's B, about away from me. Eventhough if I think about it, it wasn't A that took B away. B has never been around me in the first place anyway.
I supposed it is easier to blame someone other than your close one. That's why I'm blaming A. It doesn't help that A has those annoying look. The kind of look that makes you hate the person straight away.
Anyway, I don't think it's healthy for me to go on like this. Hating A. I mean, if I continue on like this, I'll never be able to be close to B no more. And I can't stay away from B.
Arghhhhhhhhhhhhhh!@#!%#!#$!@!@#!@@!!@ B!!!!