R.~
If the car is in your name, I would call the police and report it stolen. If it's in both of your names, I would say you need an attorney.
If you can't afford an attorney, my husband's company offers pre-paid legal for $25 a month. You can talk to an attorney for verbal advise as much as you want. I've used the service and it has saved me thousands. I also went thru a divorce and my ex-husband like to buck up on issues once in a while. It's nice to have the piece of mind that I can call an attorney at any time to see what my legal rights are.
Divorce is a hard and scary thing. Be strong and get a good support group. Try to find divorced women that are positive you can talk to. There are a lot of bitte people out there who will try to bring you down because they are negative. Try to find people that are strong and have experienced the same thing. They will life you up in time of need.
If you ever need a friend to talk to, feel free to send me a private message. I'm more than willing to listen!
Good luck