
Quoting
ashman165
Keep having sex with underage girls and you will. Oh, and a lawyer too.
As it works most everywhere, you will require her parents' (or parent's depending on the situation) consent to get married.
Let me help you out a bit though: what happened was you hit a magic number on your birthday. So, one day shagging your girlfriend was a-ok (I guess), or at least legal, and the next day it wasn't. (I don't know the age of consent laws in your state). That's all that happened.
So, let's review: sex on Thursday was fine. Sex on Friday was a crime. In the intervening two years, provided you don't wind up in jail for something or another, you could work on building a nice financial buffer (or even just get an education) to provide for her and you the life you'd like to.