Originally Posted by kilohertz53
On the other hand, the situation made for great storytelling
That's certainly true, and the very fact that we can have this kind of conversation about their motivations shows how well-drawn the characters are.
It's interesting to speculate what would happen after the end of the book. It doesn't seem a certainty to me at all that Rhett would continue not to give a damn. Scarlett is nothing if not determined, and having set her mind on Rhett, seems unlikely to want to give up on him without a fight. Also, Rhett was fond of the children - you could see them being a draw.