Everything I do is motivated by greed/aversion. How to react?

I just came to a very upsetting realisation : Almost all my motivation for the things I do in my daily life (mostly playing the piano and studying math in college) comes from bad things, such as ego, greed or aversion. Here a some examples : - I study very hard, because I wish to be better than everybody else, and prove myself that I am the most clever. In addition, I can't bear the fact of not understanding anything related to the classes. - I play the piano in order to impress people listening to me and because I am craving to get better and better. - I work hard in everything I do because I want to be admired by my friends and family. I also realized that it all leads to tension, pain and suffering. The problem is that I feel that just dropping these activities will certainly make things even worse. **The question is** how should I replace these bad motivations by more skillful ones ? In other words, how to stay motivated to do the things you love without causing you pain ? Is it even possible ?