One way to get over your fear of heights is to follow a daredevil ninety year old across a grated bridge, over a deep ravine.
Normally I am afraid of heights. I freeze usually if in that position. Recently, on a trip over the mountains, we stopped at a large waterfall. There is a grated bridge that you can walk out on and it is above a deep ravine. As I followed my ninety year old friend across the bridge, my sole focus was on her and I didn't really think about where I was.