What are my options on legal fees to be shared (debts?)

I found out that my wife was advised to take a line of credit and pay the interest only on it in order to have a supply of money for her lawyer as needed. She did this a year ago after filing a PFA against me. There is currently no divorce action in process. However I am concerned, since I built the home prior to the marriage, and it is a pre-marital asset, what could of she took the line of credit against? We have joint property in terms of vehicles, but they are all titled in my name, so wouldn't my signature be required for any additional liens?