A dissolution of marriage action in Florida must be filed in the county where the Respondent resides or in the county where the marriage was last lived out. Just because one spouse may claim he or she was forced to flee the proper county due to spousal abuse, that does not give that spouse a right to file in any other county save that which is proper under Florida's Venue Statute, as stated above.
For instance, if the parties lived as a married couple in Duval County, and one ofthem flees to Dade County due to domestic violence that party cannot file in Dade, only Duval or any other county in Florida where the Respondent resides at the time of filing.
Domestic Violence cannot be used as an excuse for improper venue.
I actually wrote my first appellate brief on this exact issue my first year out of law school and won. I could not believe opposing counsel had even filed an appeal claiming imporper venue due to fleeing from domestic violence. This is an issue on which the law is very clear.