I am still married to my husband who is a member of Local 1 Plumbers Union. We have been separated, but are still married.

Buy your own insurance has there is no legal requirement that a spouse provide insurance for each other.

You may want to contact a matrimonial attorney in your area. Your husband could be pulling a stunt or it could be the union jumping the gun. You may lose the coverage after a divorce but you will know its coming. Unless you are taking advantage of the situation, your husband is still jointly responsible for debts you incur while you are still married (and vice versa).

You should request that your husband immediately reinstate you to the plan. If he refuses, you should consider involving the Courts to require that he reinstate health insurance. This can be a tricky request because, post-divorce, you will lose coverage (though, there may be a way to require that your husband continue to pay for a plan for you after divorce). You need to hire an competent family law attorney to help you with this issue and you should not delay in doing so.