When I first came to this site, I was looking for answers, nobody really gave it to me straight, so since you asked directly, and I'm a straight shooter, I will cut to the chase.
This site is informative, you will read many things here you will relate to (at least I did) however, unless your husband chooses to help himself, there is really nothing you can do except learn as much as you can about this illness/disorder.
What I mean when I say that, is that things will start to make sense to you and you will get answers to questions you never thought to ask (again, my personal experience) but now that you know about PTSD, you're really only scratching the surface (again, speaking only from my experience).
What your husband is displaying isn't uncommon, but again, it's only the beginning! I really hope this helps, and you and your family are in my thoughts and prayers, be patient, there is a test at the end (my own brand of humor)!