divorce and military retirement?

I have a friend who's husband threatened to kill her one time in a drunken episode. She called the police and when he returned home he was arrested. He is currently in jail and due to other issues won't be getting out anytime soon.

She wants to divorce him but problem is, is that she is retired military. He was not married to her the entire time but approximately 13 years. Also he has been unemployed for over a year now due to his drinking and she pays for everything.

My question is, are there exclusions to the law where possibly he won't be able to collect the retirement. Any idea the percent he would be able to collect. He doesn't have any 401 or retirement of his own that she can tap into. I had heard that possibly if he is convicted, then he can't collect They have a child but is almost grown so leverage with the child support is not going to help either. His family is being very nasty and will do ANYTHING to help HIM!!!! Even though they've known for years about his drinking and how bad things were.

I'm really trying to help her out and any advice would be great, but seriously please only answer if you TRULY know the answer as too much is riding on this please!!!!