There's nothing like an unbearable alternative to push you through your worst fears!
But seriously, I don't mean to make light of the situation, TR. I know this is causing you an enormous amount of anxiety and stress.
But it will become easier. It really will.
What is the very worst thing you are afraid of? Is it 'getting lost' again? Losing yourself whislt driving and 'coming to' in an unfamiliar place?
If so, what things can you do to set up help for yourself if you find yourself in that situation again? Purchase a map of the area and keep it in the glove box? Write down instructions for how to access google maps on your phone? Have a list of numbers handy to call? Have some grounding tools kept in the car to help you find yourself again? have some grounding tools visible in the car so if you start to dissociate you might be able to use them to calm yourself so you don't 'go away'?
It may ease the anxiety a little if you can trust that if the worst does happen, you will have the tools to get yourself back to where you need to be again.