Medical Leave

I am out of work with what may be a serious illness and my job is trying to get me to sign a paper that states that if I do not return to work on the original date that my primary care physycian releases me then I will loss my job. The thing is that my Dr. is sending me to a neurolagist and he may be keeping me out of work for longer.
If this happens and I loss my job then I will loss my insurance then I will not be able to get the care I need and I could die.

Can they do this to me and what if anything can i do about it?

I can understand. I was just fired and I am on short term disablity. I have worked for the company for 2 years. I can not drive yet, so I have to find someone now to take me to the old company and clean out my desk. It is funny, NEVER think you have friends at work or make friends, they will turn on you.