SoL comes to mind and it doesn't have anything to do with any statutes of limitations.

FMLA does not apply so you have no protections that require your employer to hold your job for any period of time. Due to that, your employer could terminate you at any time they wanted to as long as the termination was not based on illegal discrimination. This termination wasn't.

Sorry but you are now a member of the 11% club. (over 11% unemployment in Michigan right now) with no recourse.