God, I feel so bad for Sam because I've totally been there (without, you know, the hunting). The thing that I think you pull off so well in this is the fact John's abuse isn't totally over the top. He has reasons for what he does, and while that doesn't excuse the behavior, it puts Sam between such a rock and a hard place. Is life really supposed to be like this? Is Sam just a screw up? These are the questions kids in this situation juggle on a regular basis, and you've pulled off the mentality nicely.