Your story describes the discrimination but there is not much in the way of evidence that the discrimination basis is the medical condition. The boss' comment about absenteeism is all there is. But that might be enough. I suggest you make an appointment with a labor litigation attorney. That attorney's questions and your answers might identify some other evidence.
This answer must not be relied on as legal advice for the reasons posted here: http://mcgyverdisclaimer.blogspot.com . And I am not your attorney.
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