My apologies. I don't know what may have happened to your initial response, but I didn't receive it.
This appears to involve disability discrimination, not discrimination for taking FMLA leave. Both are illegal as you may know. While your addiction does not protect you from disciplinary or punitive actions by the employer, your treatment does give rise to protection from such conduct by the employer typically.
Because the adverse actions began after you informed the employer of your treatment, that would normally give rise to a claim for discrimination under the ADA, for which you should file a complaint with HR unless filing the complaint would be futile.
Your next step, if the issue is not promptly resolved, is to file a formal complaint with the state fair employment and housing commission in an effort to resolve the matter.
Here is a link that explains the law further (use keyword "alcohol"):
It is best to also retain a local employment law attorney to represent you through this process.
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