I was terrified of driving too, however, you should see if you can find someone who will teach you at your pace (and be willing to push). Instead of driving on a busy road, or a road at all, find a large, empty car park to zoom around in (or an empty road). That's where I first learned to drive under my Dad's instruction.
I wonder if sitting in the driver's seat and imagining yourself driving would be helpful? In any case, the best cure is to face your fear head on and to never give up, especially if it is important to you. As my sig says, don't not do something because it will take time, time passes anyway