Tell her to pack her shit and get the fuck out. You're a pretty stand-up dude and don't deserve that kind of bullshit and maybe some tough love will pound some common sense into her. Or a couple weeks of living with her mom again. Then again I'm usually dead wrong when it comes to emotional shit and maybe that would just give her mom more opportunity to whisper poison in her ear. Definitely not a dilemma I'd want to face.
She's a teenager. Don't let her walk all over you, and don't hold it against her if she grows out of it. Hormones, friends, and stupidity are par for the course.
The trick is realizing marriage is a 100%/100% proposition. A lot of people say 50/50 but that's a recipe for disappointment. Each one has to put their all into it but everyone doesn't have the same 100%. If done correctly each partner will think they're contributing more to the relationship. But that's only because with the other person taking care of business, you are focused on the parts you do.