Although your perceived problem has a universality about it, you'll find this is primarily a United Kingdom site, so you're not likely to get a lot of answers, especially relating to the differences between the Corn Husker State and the Show-me State. (I live in the U.S. as well).
Let me just say, that at your age (believe it or not, we've all been in your shoes, one way or another) you generally are seeking long-term solutions to short -term problems. In the scheme of things, living in Missouri isn't that big of a deal since you need to be focusing on education so youcan have a future. As painful as you think it is right now, try living on your own and trying to make your way into a better situation. If you'll give the problem a little bit of time, a little bit of adult thinking and a whole lot of future outlook, you can see that life is just a series of compromises and if you'll make the right choices now the future will be a whole lot brighter.
I can only imagine how painful and disruptive divorce can be, but this, again, is a short term problem. Find some backbone and pay the unfair price with which you've been saddled, and I guarantee you'll look back and see it was the right one... The only caveat would be if you are in an abusive situation... that demands a different answer. Best of luck!