River, I've been asking myself my whole life what broke his spirit, and I keep coming back to co-dependency being passed from generation to generation, much like physical abuse is. Maybe it's a learned behavior. I never met my grandmother on my father's side, since she lived in South Africa, but I wonder if she was an N, and he knew no other life. He married one himself, and simply accepts it. I see this in my brother. He has also married an N, and puts up with an unbelievable level of abuse and control without ever complaining. He grew up in an environment where the wife had 100% control over the husband, so why would he question it? It's what he knows.
They say that most men who physically abuse their wives had fathers who physically abused their mothers. They grow up with it, accepting it as "normal." I suppose Co-D might be the same way.
My parents married at relatively young ages, so maybe my father never had the chance to really develop as an adult before she came along and "mothered" him. Just a thought.