Because the car is jointly titled, you each have equal rights with respect to it. If it was purchased during the marriage, it is considered marital property, and thus subject to equitable distribution by the divorce court. As a practical matter, however, this very rarely happens for the following reasons: 1) in my experience, about 90% of divorce cases settle prior to trial, and ordinarily the party driving the car keeps the car as a part of the agreement; 2) most cars have little to no worth (you have to compare the fair market value to the amount owed on it), therefore there is no asset to divide, and the party in possession ordinarily agrees to make all of the payments in exchange for keeping it; and, 3) if you have grounds to request a protective order, the court can award you use and possession of the vehicle for up to one year, which is usually a sufficient time frame to get your divorce case filed and resolved. Even if the car has value and could theoretically be sold to divide the proceeds, you are probably fine because in negotiations, you could make a concession elsewhere to balance out you keeping the car (a slightly lower claim to his retirement, for example).
Pending a court order, he cannot make you sell the car. You, alternatively, cannot get him off of the title until he either agrees or a court orders him otherwise. What to do if he takes the car from you in the meantime? Most local law enforcement offices will not get into the middle of what they see as marital property disputes, so my advice is keep the vehicle somewhere he cannot locate it, until you reach an agreement, in writing. You are under no obligation whatsoever to return the vehicle to him at this time, unless there is a court order that specifies otherwise.
Finally, ordinarily neither party in a divorce case is entitled to dissipate marital property, meaning liquidate it and keep the proceeds (limited exceptions sometimes apply). If you believe he is either currently liquidating marital assets, or intends to do so, you can request injunctive relief with the circuit court to prevent this.
Your case may be somewhat complicated because you are active duty (including where your divorce may be properly filed -- keep in mind that my advice pertains to Maryland, and your case may not be appropriate to file in Maryland court). Feel free to email me directly if my answer raised more questions than it answered. Good luck!
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