They'll be frightened if you don't talk to them about it, and some close family and friends are more open and understanding than you think. Especially if one or more of them is also a veteran.
The key is "if they are a veteran". I would not go into detail with my Mother, for instance.
Telling folks a bit of how it was, surely, can be useful. However, depending on the level of war trauma exposure, the vet can get into a place that he/she may need help getting out of. We get to see some pretty ugly stuff, far beyond what the casual civilian ever sees.
I do realize that this is 2004 and not 1964, but I find many folks, still are pretty naive. The interactions can be damaging for both the vet and family/friends.
I guess I would say to excercise caution. If you don't find a place at home or with friends to talk about this. You definately need someplace to do that. The consequences of not processing what you just were exposed to, are very long term. Unfortunately, I learned that through personal experience.
It was his comments about the hyper-startle response and not feeling safe without a weapon and protective gear that perked my ears up.
In any case, the robust welcome home goes a long way in helping with the transition from warrier to civilian.