FitChik -- I can't speak to H's salvation or to your need for him to be close to your god. I have no god. But I CAN speak to his behavior upon deployment.
I did OEF/OIF from Feb 03 to May 04. Your story is common one, I'm afraid (at least 6 Joes under my command did the same thing).
Don't know your sitch re: military service yrself, but I can tell you this -- life in Iraq is life in a parallel dimension.
Even now, I assume, with the violence well down. It's not a "normal" deployment. You live in a weird kind of suspended animation. The World doesn't exist. It's all about the 50-meter target.
Some of my Joes filed for D because they didn't want / feared their spouses spending all their money (ALSO not uncommon, I'm afraid). Others filed because they had to go thru this kind of "I'm already dead" thing just to cope with what was to come.
I don't know if you can DB from 8,000 miles away. But you can try. Don't get into R talks on e-mail -- you don't read e-mail the same way over there (trust me on this one -- you should see some of my W's e-mails when I was there). And the Joes don't want to get "how terrible it is at home" letters -- that's so common, even "Doonesbury" had a series of strips on it.
Don't have R talks on the phone -- redirect -- because as soon as he signs off he's going to pull out a smoke and bitch to his buddies, who are all going to enable him.
Keep it light. Keep it generic. Fill him in on his favorite team. Ask some of his fishing or hunting buddies how it's going. Give him things to look forward to back in the World that are "his" -- "hey, Chuck says he's restoring an old Chevelle and wants you to help him when you demob." That sort of thing.
In other words, you have to keep the M alive by acting AS IF you understand that it's dead. As long as he doesn't feel under pressure to keep the process moving, you'll live to fight another day.