I put up something a while back about being a military wife. In it, I noted the fact that Paul's job sometimes requires him to go away for long periods of time and that his work can sometimes put him in harm's way. I noted also that these things are true of friends and relatives of ours who either travel full-time, or are police officers or firemen, who work 30 on/30 off schedules far away from home, etc.
The one difference, though, at least to my knowledge, is that those guys are usually a phone call or text away, which cannot be said of Paul when he's off doing far-away-medium-work or long-work.
The distance is more palpable when you can't just bridge it whenever you want. It's been what, half a day? And I can already tell the difference - I'm pretty sure this will be one of the harder things to get used to.