A friend recently recommended the book Finding Your Own North Star, claiming the life you were meant to live, by Martha Beck. It is a great book for those who may be questioning a career change, or if you are getting tired of the same old, same old.
There is one very powerful exercise called Story Telling.
First, write a brief time line of the major events in your life. Read it over, and see whether you've written a happy story or a sad one.