Divorce and Pain...

In The Great Divorce I am most intrigued by the conversation between the woman Ghost and her Spirit brother about Michael. It is obvious that the Ghost has selfishly held on to Michael and his memory and that has kept her from entering Heaven. However, there are some points throughout the conversation that do not settle with me and, seem to be contradictory to Lewis’ ideas in the problem of pain.
First of all, since the woman is obviously experiencing great loss, I am not sure what the Spirit is trying to accomplish by telling her that it was God who took Michael away for both their sakes. I think that would have done little to entice her to reconsider her actions. Along those lines when the spirit says in reference to Michael dying, “the only remedy was to take away its object. It was a case for surgery,” I have to wonder what Lewis means by this. In The Problem of Pain Lewis seems to develop the thought that all pain comes from the broken and sinful state of humanity. That God does not create but allow the pain. Also at times in the problem of pain it seems that Lewis even suggests that God suffers with humanity.
This makes me wonder than what Lewis’ view actually is. Since the woman obviously did not wish Michael to be taken away, it would be easier (and possible more beneficial to the woman) to believe that God had not done it but, just allowed it. However, the Spirit directly says the opposite and suggests that it was necessary. So my question then is, does God allow sin and then create pain in order to possibly help one realize their sin? That does not seem right with me either since that is just God playing a game of chance.