To amend my answer, I suggest this: Find inspiration. It is too difficult for most of us to sustain momentum in practice without this crucial element. Find a teacher - myself and others here in the Northern California, and you'll find someone whose passion for the guitar became the main focus of his or her professional life. Ask them to play and watch the dance of fingers on strings see how their concentration shifts into high gear as they seek to do justice to the music's potential. And of course, go to concerts.