Join a union and ask for their advice. Even if there's limitations on what they can do as it seems the process has already started, they'll still be able to advise on what you're able to do deal with constructive dismissal.
Look for another job. It's way easier to find work when you're in work and don't have to explain why you're not at your last job.
Do both of these things. Your health isn't going to benefit working at a place where you're not wanted, even if they can't just fire you.
Oh and if you're in a country where you're allowed a representative in meetings and you can take one, always have your union rep there, no matter how friendly it seems.
In Britain we have a pressure group that's inexplicably on TV every other week pedalling this lie and the one that corporation tax hurts businesses. (Corporation tax is paid on net profits, so businesses only pay if they can afford it).
What's funny is they're called the "taxpayers alliance" yet their narrative suggests none of them actually have any experience of paying tax.