If it is public record and what is posted represents the truth, there is not much of a case. Truth is an affirmative defense to claims of libel/slander. If suit is initiated or demands are made, you should consult with an attorney in your jurisdiction. Good luck.
This answer is for general purposes only and does not establish an attorney-client relationship. Consult with an attorney if you need further assistance.
I agree with Matt and Christian.
You and your ex your friends need to simply flag/report the account as being fake to Facebook. Facebook will take it down. Problem solved.
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