Hi, Oh, I am so sorry.
He is experiencing survivor guilt. Survivor guilt maintains itself to provide certain meaningful feelings. It prevents the event from being meaningless, and keeps him from feeling helpless, by a constant reinforcement of his negative feelings about himself.
Techniques counselors use to deal with patients and PTSD does require talking. It is important for him to tell his story over and over, as many times as needed, until it no longer has such a powerful hold. He must also have an environment that feels safe to talk in. Support groups are great if he would go. Encouraging him to challenge irrational or skewed thoughts will help him handle his own feelings better, and grasp a more realistic view of what happened.
As for his anger, It is always the one closest that gets the outpour of anger. You must talk to him about how this is effecting you. And let him know you will not tolerate this emotional abuse. You and he are survivors as well. You must let him know how you are effected by this, and give him options for change.
You may want to consider talking to his supervisor, and ask him/her to talk to him about getting back into counseling and on medications. I am sure this must be effecting his job? The department wants healthy workers both for themselves, and for their employees. Please let me know if you have further questions. Thanks, Gina