Legally, it's your car and yours alone. It was a gift and you have never done anything to change that status (e.g. jointly titling it). That being said, your local police, if called, would likely say something like "Ma'am, you're married, so everything is joint property."
If you want to protect your interests, you may have to file for divorce.
Answered on Jul 06th, 2014 at 7:08 AM