I need to leave my house but my car is under my mom's name

My mother is an abusive alcoholic who I've been planning to get away from. She bought a car about four years ago. When I was of age to get my permit she taught me to drive in it. Eventually I got my license and Ive been driving it regularly. About six months ago I bought an older truck, similar to one she owned years ago. We made an agreement to trade. She registered it in her name and convinced me that it would be best to keep both cars under her name to minimize insurance cost. I agreed because she would act aggressive towards me when I suggested putting it under my name. I tried to bring this up on several different occasions and each time she yelled and threatened to take it away from me. I've always submitted because I figure, legally, it's hers and she can do whatever she wants.

But now I'm making plans to discreetly escape this hell house. And I love that car. I've bought tires for it, paid for new brakes, and other things. I do not have reciepts for these things however. I can't imagine leaving this car behind but there's no way she'll let me put it in my name. Is there any way around this? I have no money to buy a new car immediately and it's Winter so walking everywhere isn't an option. Why do they have to make everything so hard? I know she is afraid of me leaving her so this is how she's trying to hold me down. Thanks for any advice guys it's really appreciated. More than you would know lol