Harassed since standing up for an agreement for benefits which was later denied then allowed.

My family and I were moved from near Richmond VA. back to Ohio (by the employer and housed as agreed) from which origionally came. This company had promised health benefits through the previous HR Manager. The New HR manager had started the day I arrived at the plant. Since I had been laid off and was working as a contractor and had not needed the COBRA program I did not pay for it. The time that elapsed while I was uninsured was 92or93 days. The HR manager said she could not help me. I sent an E-mail to corporate which upset the plant manager, HR Manager and My Manager. I received a written letter stating that I did not act properly. Since this time, I have been written up 2 more times, but I never really receive a reason, but the the insurance statement always comes up. Recently, I was wrote up again, after our French Canadian,(non-US citizen)plant manager stopped at my office and made many accusations which were false. I did not argue with him but went to my Manager and complained. In two weeks I received another letter stating that I have 60 days to correct my behavior. (My Manager had just gave me a superior rating during my review which was verbal and did not give me anything in writing)The letter pretty much stated that I do nothing for the plant. They also stated that "People in the plant felt that I was not technically capable to perform my job" When I asked who, they have and always state "We can't tell you that" I taped this conversation with their knowledge.