I just defended my dissertation yesterday. It took me about 4 1/2 years. Indeed, I thought about quitting over and over again. motivation will come and go. relax when you dont feel like working on it. Look at this as a productivity pause. It is a natural and normal psychological state that usually comes after a burst of work. You will not be able to stop thinking about it, but use this time for exactly that, "thinking about it". Thinking about the next problem you have to work through, or the next page you have to write, etc. This is still considered working on your disseration. Of course it is always better to pick it up and do a little something every day (expect when you really need a break, and you will know when that is). What you are experiencing is completely normal...hang in...Dr. Ellis