First off, you are making this up for cheap entertainment.
Secondly, to answer your questions:
She does not own the car. The lien holder was on the title all along because they own the car. When the loan is paid off the lien holder signs off on the title to the new owner, in this case your girlfriend. But since the loan is not paid off, she will not get the title and the owner has the legal right to possession.
Read the contract she signed when she took out the loan. She violated the terms by not paying and the lien holder has the right to take the property back. All she has is possession, possession of a car she does not own. The lien holder has the legal right to take her to court to force the release of the car; they may or may not take that step. If she refuses, she could be held in contempt of court and I don't think she really wants that.
You have no rights here. Seeing all or part of a car owned by someone else is theft.