I'd say many people don't "buy" into "do everything in your capacity to keep the wheels together". Some are willing to do everything, but only up to a point.
I wouldn't stay in a marriage that requires me to struggle to make it work, again, and again, and again. Many people stay because of cultural and religious norms, and I think that's a shame. We do only have one life, and it would be a pity to live in misery with someone when we could be happier alone or with someone else.
But this story isn't as much about people who break up as it was about people who cheat and still don't want to break up. It is about how being married doesn't mean we'll be perfectly content with everything we get in our marriages, from a sexual perspective, and what we are supposed to do to avoid getting to that point where we feel betrayed.