Instead of looking for your purpose, wake up every morning without fear. Wake up and face the day, tell yourself that you want to be present and fully experience everything it has to offer. And then... "when a little flame lights a fire under your ass" you will realize you have suddenly found purpose. I am exhausted, but I think for the first time in a long time, I have felt some kind of a sense of "purpose."
Side Note: If you were slightly offended by my little flame quote, you should not go see the Broadway show Avenue Q.