Nat,
I am so sorry that you are canceling your family vacation, but would it be at all possible for you and your husband to go away for a few nights, just the 2 of you? With him being away for so long it would probably be good for the 2 of you. I would hate the thought of being there without my boys, but I think I could get over it!;)
It sounds like you do an amazing job with your boys, and they are lucky to be so close to DL!