How do I get out of the relocation contract I signed?

The company I work for moved me to Illinois 16 months ago. In return, I signed an agreement stating I would pay back relocation if I left within 2 years. Moreover, all monies have to be paid back within 1 month of my leave date. I made a BIG mistake and didn't read the fine print. It turns out I have to pay back EVERYTHING if I leave before the two year period. This job has been awfull and it's to the point that it starting to make me physically ill. I can't afford to pay back the money because the salary is not comensurate with cost of living expenses and I have wracked up a bunch of debt just by trying to keep a roof over my head and gas in the car. I approached HR about my concerns which has only caused more friction between myself and management. I feel so trapped. Is there any way I can get out of the contract?