You will have very little success getting reimbursed for your wife's portion of the medical insurance. You are still married, even though you are separated and from your question, it does not appear that there is any case filed for divorce. Therefore you do not have the backing of the court or any other authority which would require her to pay you. Additionally, if your carrier learns that you are seoarated, it is possible that they could refuse to cover her any longer. Many insurance carriers no longer cover spouses when they resides separate and apart. You need to look into this.
Generally, I agree with the prior answer. The state imposes a public policy that one spouse has a duty to support the other. Unless you and your wife have a written agreement that says she owes you her share, then you won't likely get it back. The only way to end that obligation is to file for and obtain a divorce (which may or may not have other financial ramifications based upon the other facts of your marriage).
My answer is based upon the limitations you have given in your question, and may not be complete as there are numerous exceptions to every legal claim which requires a full analysis of the facts and circumstances of your case to discuss in detail. Please see a lawyer in your area and do not rely solely on any answers you receive from this web-site.
I agree with the previous comments. I want to add one additional question and comment of my own. Is there a reason that you have separated and not sought a divorce? If you are now FL residents (living here more than 6 mos.) Then FL law will apply to your case. You need to consult an attorney to go through the options and evaluate what is the best course of action for you. My firm offers free consultations.
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