So far, we haven't made it that far - well, once, but that was at the tail end of a trip and I didn't count as "having been home, yet," so there was no sense of it being an overnight away from home.
What I've noticed about these feelings (when I have them when my wife is with our partner, AM, or when she tells me how she felt when I was with AM) is that they revolve around feeling lonely and alone and like I'm not in the know about what is going on. We have success with distractions (a good book for her, being on the forum here for me) or good friends, or just doing the work that our jobs send us home with. Next thing you know, time has passed.
But that doesn't help the moment that might be the tough one for you - going to sleep. Can you figure that out, walk through the whole event in your mind and see where the trigger point is? Do it with your wife, talking through what she's doing, perhaps (if that's not too much information for you), and maybe you can find the point that all of you could understand better, and it would help you out...