Lionspaw, your post was so heart wrenchingly honest. Just want to say how I feel with you.

Actually, I did the same thing to my Mom, by moving to Germany. When I think back, I'm so grateful to her that she made it so easy for me, without laying any guilt trip on me. I guess that's one last big present, but valuable present, a parent can give their child when they leave and live their independent lives. Easier said then done, I know, and I have yet to follow my own advice when my son comes to say good-bye.
My Mom took a real-estate course when I left. I guess that was to fill the gap as well. Hopefully you have the opportunity to stay busy and distract yourself.
Lionspaw, I wish you from the bottom of my heart, lots of new found energy and the opportunity to fill that gap with wonderful new discoveries.