What are existing theories on competing wills in the mind?
Instead of pointing you to existing theories, which is (1) too advanced for you to understand at the current level of knowledge, and (2) too focused so that you don't have a big picture, why don't we just suggest you to read a textbook about cognition? It will solve both problems at the same time. 

I recommend the book Cognitive Psychology, written by Strenberg, as the starting point. Cognition: Exploring the Science (author: Reisberg) is also a good one. If you are like me, you will realize how to make the question clearer just after some first few pages of reading.