A few trinkets I've gleaned from relationships with women:
Any man who claims to understand or know women is only deceiving himself.
Any woman who hasn't figured out how to use charms on a man to get him to do things he wouldn't otherwise do hasn't read her own manual.
Every woman is completely different, and if you want to begin to understand them get a cat. If you can put up with a cat doing whatever it pleases, tearing up things you like and sticking its claws in you whenever it feels like it you might be able to get along with a woman for the rest of your life.
It is only my personal experience, and I don't want to speak personally about every woman on the planet, but I have universally observed that they will act first in their own interest when the chips are down. Especially once they've figured out trinket #2. Not that many guys won't do this as well.
If you think you and she won't change dramatically as individuals in the next 2, 4 or further years you've got another thing coming. It is remotely possible that you two will change in the same directions, but highly unlikely.
Wait till you start meeting girls around the age of 21, when they know how to get things out of a man, can get into bars, and somehow get a notion in their head that they are gown up. That's a nightmare!
Her moving away from you now could be the best thing to ever happen to you. Silver linings are funny like that.