Hi, well I can kind of relate..I also have GAD, my husband took a trip to Italy last year, was gone for 17 days. At first I didn't know how to handle him being gone.I felt pretty anxious about it, but as Cuchculan previously advised, I decided to keep busy. I did a lot of home maintenance work. Our front porch overhang had chipping paint, I took a ride over to Home Depot, bought a gallon of white paint, took out the 9 foot ladder, and started scraping away. Then I painted the overhang and the front door. I then went to the dollar store, bought some pretty flower pots, and planted my impatiens (that needed to be planted), put them on the porch after everything was freshly painted--it was just beautiful. I gave the inside of the house a major dusting and cleaning too. When he came home it was a warm welcome for him.
So, try keeping busy---the time will fly by, before you know it he'll be back home :)