Because we are human. Because we always want more. Because we want what we can't have. Because what we want changes from moment to moment. Because we are still selfish children.
We get our priorities all fucked up, and lose sight of what is important. We lie to ourselves, and to those we love. Sometimes, we even think that it is a noble thing, when we do it.
I don't have blinders on anymore. It's more painful this way, but more honest. And Closer was one hell of a movie.