The good news is that I see a definite path to get there. I have a much clearer understanding of both how to complete a dissertation and what I want my dissertation to be about. Now it's just a matter of crafting my research problem, establishing my methodology, collecting my data, interpreting the results, clearing everything with my committee, and writing the whole thing down.
I've also been blessed with some excellent and supportive fellow students. It's really nice to have both a cheering section and a group of people I can consult (and commiserate with). We will get this done.