Why should he apology or acknowledge anything? he is not bound to your main party member by anything but a mutual objective. remember : he tried to kill you in your first encounter, and didn't apology either. Its just the character writing. he doesn't give a damn about you. he doesn't care about the feeling of your main character.
Its just his personnality, the way he is written. See it from a role playing point of view and don't get offended by minor slight like that. If you're still dissatisfied by his behavior, you can still kill him.
I feel like you take everything too personally . Its just a selfish, evil character in a video game.
He's definitely a pompous ass who excuses everything he does. One easy way to get him to apologize for his behavior is to agree to let him suck your blood if he apologizes to you. And when he inevitably scoffs at your request and does a half-assed apology complete with an eye roll, another dialog choice should pop up that allows me to pick, "I need you to mean it." I think it's a great way to still show off his personalty, but also evens the playing field a little bit. They can even go the extra mile and have his responses based on his current approval rating. If he hates your guts he can storm off and get blood elsewhere.
