Good for you and kudos for staying strong!!!
Might suggest you go ahead today and insure that jeep like, yesterday. I think all states require at a minimum liability insurance. Your license could be suspended for not maintaining insurance, and it may be already. Most of that is done electronically if your insurance is cancelled they notify the DMV immediately. Then YOU get to pay a nice hefty reinstatement fine. If he gets in an accident guess who gets sued? You. If he gets a DUI driving your vehicle guess whose insurance skyrockets through the roof - YOURS.
Calling the police to try and get him to "stop driving" isn't going to work. They can't make him stop driving. I suppose you could call them and warn them he is driving drunk and they might be able to catch him and put him in jail for DUI - which may or may not result in a very expensive ticket for you for not having insurance.
Cover yourself here - don't end up with a headache you don't want, need or deserve.