Take her out to a empty Walmart Parking lot? Helps many people with a fear of driving if they go a few times or more and drive without worrying about hitting anything.

Its all about finding something that isn't as scary as the other, and then over time getting someone used to the scary thing. First with the wife biking only on bike lane roads, then we have a couple of 4 lane one ways in the down town, that got he used to it as the cars stick to the left 3 most lanes anyways on those roads. Then finally getting used to no bike lanes, and cars all over the places.

Doing a little more every time, even if its not a lot of difference from one day to the next, goes a long way to break people's phobias.

Jim