I'm unsatisfied with my valentine's day gift
What did you want instead as a gift?
I wanted a brand new car
I'm sorry you didn't get what you wanted, but a gift is a gift no matter what It's the thought that should count and you are being unfairly ungrateful. No one should give you gifts if you are not going to appreciate anything.
Why is it wrong for me to demand my partner get me what I want otherwise I would dump them?
Because you are nothing that special to the world like most people, and just accept what you are given. Be humble and just be happy you are together. That's all that matters in the end.