And so...? At the end, he doesn't owe her...? Well, I mean it would be really unfair to hate her for no reason - It's not the fault of his mom he lived under her shadow -, but he's hanging from a thread that she can easily break at any moment.

Ok, your mom seems rather cool from a perspective. Obviously rather creepy. I don't think you should be mad at her for her nature, it's just that way as vampire. And she did not hurt you or abused you at all.

You're allowed to have resentment if she does "something"- like turning you into a vampire - without your consent tho.

Honestly, the fact that she's his mother isn't an argument. The fact that someone is blood related will never be an argument.