Hi, MarnieB39,
My first Post here was about my double vision. Mine is caused by a lesion through the middle of the occipital region of my brain and is unstable and permanent (no prisms to correct it). I, too, have lost my last little bit of freedom driving gave me - even being a passenger is nauseating and disorientating, so I know how you feel.
With me, my brain chemistry stops me wearing an eye patch. I lose all peripheral vision, then everything 'greys out' after a while as my eye dominance switches from right to left. What I have that helps a little is a pair of glasses with the left eyepiece covered with translucent plastic film.
This was recommended by my Opthalmic Consultant. It is fogged enough to blank out the double vision, but still lets in light so I am not so disorientated. And it is more aesthetically pleasing than a patch.
I truly hope your problem can be resolved as rapidly and completely as possible, anything affecting one's sight is one of the fastest and most complete ways to isolate the unprepared.

Dave.