So I usually explain to both those with and without balls that the dissertation is my third priority behind 1) the family and 2) the job. The order of importance will never change. My priority list may not seem to be a full plate to some, but my family life can be a bit different than it probably is for others much of the time...
For example, read the Wife's post from this evening. Then ask me again why I'm not done yet. After an evening like this, I think I have a good reason to let my brain fry in front of the TV for 90 minutes. I just don't see a problem with it. So maybe I won't make much progress on the dissertation this evening, but I did help comfort my kid as he mentally tortured himself for 45 minutes about an issue with our telephone that doesn't really exist. Being there for him was far more important than working on the fucking dissertation.
I don't intend to use my son's disorder an excuse. It's part of the balance of our lives, and I wouldn't give up that balance for anything. In spite of Moose's disorder, or my "mixed-up" (ha) priorities, or any of the other stuff that life has brought our way in the last several years, I am still making progress on TFD. Wife and I are still married. My kid is growing like a weed, and he's healthy. Bottom line, I am being true to my priorities, and the process is working for me.