Since Kentucky is a no-fault state a spouse can technically start dating at any point in the process. However, please be advised that if you are spending funds that are deemed marital on a new girlfriend or boyfriend an argument could be made that you are dissipating marital assets and you could be required to repay those funds to the marital estate.
You may not remarry until the court has entered your decree. If you marry prior to the entry of the decree, then your new marriage is void.