"If you are a writer, then write"
And I thought it just about summed up the dilemma most people have. Either they don't really know who they are, or they deny who they are - therefore, they aren't doing the things that would truly make them happy. You're thing could be anything - writing, acting, giving, painting, talking, teaching - and if you are not actively doing that thing, then you are not actively living your happiest life.
Think about it for just a second...what is the one that you have always done, that makes you happy? It's probably a big word - like "giving" or "teaching". That means to live your happiest life, you would have to "give" or "teach" - and to make the most money you can make, you'd have to do those things also. Now, teach is a big word, with lots of possibilities - you could be in the "teaching" profession like a school teacher or college professor, or you could teach something - through unconventional means - one-on-one or group settings. It could be any industry - all of them require some level of learning and teaching. You could help manage a training organization or do teaching seminars - there are hundreds or even thousands of possible combinations. But "teaching" is at the core.
So you need to think through those things, find that one big word that describes who you are and what you love to do, then investigate how to integrate that more into your life. Our goal should be to live our happiest life and not settle for what is handed to us.