Developing and sustaining the will to complete a complicated, long-term project is a habit that will serve you well in other areas of life. As you print out chapter drafts, bibliographies, and such, put them in a notebook with dividers for each section.
Do you get more done on campus or at home? My PI had been heavily involved in writing each of the papers that went into my thesis, so the need for his input was less critical.
Some people write chapter 5 before they write chapter 4. While you want to keep your advisor and committee informed about major changes in your focus, in most disciplines you do not have to follow strictly the research and writing plan that you suggested in your dissertation proposal.
That may work fine for you, or you may decide that you would prefer more frequent contact.
By tackling the quick revisions first, I felt that I was making progress, which helped me stay motivated. The appendix provides a list of action words to introduce quotes, a list of suggested items for inclusion in a research proposal, a statistical decision tree, a list of general action verbs, and an impressive annotated bibliography of books on writing, research, confidence, public speaking, computers, and more.
I also read some books on writing. Write every day As the saying goes, even if you wrote just a page every day, you would have over pages after a year--that's almost a finished dissertation!