If I'm reading this correctly, you think she is delaying for her own good, so that she can use the car until she can move and not need it anymore? In that scenario, I get why you wouldn't want to continue this arrangement and why you'd rather end it now and not have her taking advantage of you. But you don't know right? And you can't know either, right? So give it a big ole woosa and let it go. If you want to divorce her do it. If you don't want to divorce her, don't do it. The car is not the issue, the idea of her leaving you and taking advantage of you while doing so is.
As far as driving the knife, yes that's normal IMO. It's usually done when the LBS gets his or her hopes up.
H 34 W 29 BD 3/12/18 Divorce Busted Spring 19
It is not things that bother us, but the stories we tell ourselves about things.