Can I file a domestic violence case against my abusive ex-fiance in Florida?

Yes, you could file a domestic violence case against your abusive ex-fiance in Florida. The burden would be to show that there is a reasonable fear of harm from that person. You could file for a domestic violence injunction which would prevent that person from having any contact with you or coming within 500 feet of you. If they violate that, they could be charged with a crime.