Probably extreme travel is not a good category. Most of my friends and relatives view my solo backpacking trips as extreme so extreme is in the eyes of the beholder.

Recently I have read that book, the Bicycle Diaries by David Kroodsma and Wild by Cheryl Strayed. In each case the author starts the trip by severing ties with emotional partners in order to start the trip. Breaking up with your girlfriend/boyfriend/spouse seems to be a common starting point. I am sure that hundreds if not thousands of folks start long trips or even short trips as a way to change scenery and gain a different perspective without cutting home ties. I know that when I start a trip it is with the understanding that I will return to my wife at the end and it is no way a reflection on our life. She goes to many things like retreats etc where she gains perspective.