Maybe what you have is latent hostility towards a woman your father chose instead of your natural mother? One of the hardest things for ANYONE to do is see life through unclouded lenses... Look at the situation and be honest with yourself about what it is that actually bothers you. Incessant talking is not such a bad thing, nor is being unknowledgeable about a particular thing, ie, the car. Have you considered that she noticed your enjoyment with yours and wanted a common ground with you, so now she has a car that she can customize to make her own as well?
i know nothing of the two of you, but I can say it appears based on the information you've provided, is that you need to:
Take a breath, take a step back and think before you act...
There's an old saying...
be careful with your thoughts
your thoughts become your actions
be careful what you do
your actions define your character
the the other thing is we all take the path of least resistance... You wanna be with your dad, but can't stand the woman in the house with him. You'd rather be with him but would want to be with your mom... Yadda yadda yadda
Just make a decision and stick with it, but don't then beeeeatch about it. We can only take responsibility for the decisions we make, not necessarily the consequences of those decisions, but they're not anyone else's fault, problem or issue, but our own.
now there... That all is a healthy dose of reality, accept it or deny it, which even you like, but wake up, make your first adult decision and get on with your life!
: )