Forget fate, forget destiny, decide your own purpose. Don't like your purpose? Change it. What you do is your choice. Noone should be able to decide your purpose without your consent. Someone may decide for you and you may not have a choice in the matter. Doesn't make it right though. My purpose is mine. And your purpose is yours. And if you don't know your purpose yet then that's ok too. Some people can live their whole lives without one and that's just fine too. But in the end your purpose, if you have the choice, is whatever you decide it to be.