I have the study in one of my files somewhere. Average reintegration times are as follows:
Airforce members are reintegrated on average within 6 months of leaving the service regardless of career length (corporation)
Army/Navy - One year of reintegration time for every one year of service (military branch)
Marine Corps - Never. (Cult)
and ask any Marine, even if you could press a button to reintegrate us, none of us would want to. Who'd want to be a civvie any way? Especially when you can be a gods damned United States Marine instead.
Now Papersatan is both right and wrong, the group identity of belonging is an important part of military training, you need to get along and share some form of common experience with your "team". It lacks depth however and cannot explain the Marine Corp's culture, and it's long term impact on all who join her ranks. You will, in your day to day lives, meet soldiers, sailors and airmen who if they feel like it or you buy them a beer, they will tell you about when they were in the service. A Marine in a similar position will tell you "I am a Marine". It doesn't go away when we take the uniform off, and even for our sister services no amount of "deprogramming" (which isn't a term I'm comfortable with at all) can take it all away for the fact of one simple fact.
Our first duty is too each other, and until I can find a group of civilians made up of individuals who'd take a grenade for me without a second thought I see no value in compromising my values, changing sides or switching teams, to be some unprintable civvie again.