Forced to resign or be fired without cause, I resigned, but now being held to non-compete

I signed a non-compete as a standard part of my offer of employment. I found myself in a situation after one year of employment where I was to either resign or be terminated without cause. I chose to resign but my employer will not release me from the agreement. The non-compete is for one year and a 20 mile radius from my facility. I am in the medical field, but not a physician, and can only practice in a collaborative agreement with one. There is only one such practice, other than the one I left, within the 20 mile radius and the next closest one is 60 miles away. What legal options do I have, if any, to get them to release me from this agreement? Seems like they don't want me to work for them and will not allow me to work for anybody else.