You should talk to the doctor who is prescribing these medications. It is a tremendous amount, and unless he is in excruciating pain, I am sure his doctors would not want him to have this much medication. He can't get addicted this quickly unless there is a history of addiction, but he might be quite frightened about his accident and is using these pills to quell his fear. You might talk to him about that.
have you ever heard of Al-Anon? you might want to call information and see if there is a group in your area.
good luck!
amber