I discussed that somewhat in this post: Common historical myth/misconception: Anne Boleyn caused Henry VIII’s break with Rome.
I think that Henry VIII was a guy who wanted total, unquestioned control over his life and country. The church was trying to exert control over his personal life, and church land within Britain was taking away from his ability to control (and monetarily benefit from the total control of) Britain. So I mainly think that Anne Boleyn provided a convenient pretext to separate from Rome.
So really, I think he was a man thinking with his wallet (so to speak) above all else.