While I respect their attempt to give their message, I can't say much for their propounded method. It would have been far more realistic for the woman to pray for courage to confront her husband. Praying for her husband was a good thing, but God is not a fairy godfather who will solve all our problems if we wish hard enough. Praying for someone and hoping they will change on their own appeals intensely to pacifists and others who hate conflict. It allows them to keep rolling over while feeling like they are doing something.
I should say that the most realistic part of the film was her daughter following in her mother's example. Children are excellent mimics, especially where their parents are concerned. By taking action in her own spiritual life, she influenced that of her daughter's.
Then again, I'm Presbyterian. I'm not exactly the best authority on spiritual power. Had I been a friend of the protagonist, I would have advised her to tell her husband plainly that he was hurting those he claimed to love. I would also have advised her to pray for courage to that end.