Right. It's not a question of "morality" though. It's just a question of whether they are both getting what they want out of the relationship. And if not - and they can't figure out how to fix it - they should just end it, and move on. There should be no shame in that.

The underlying problem is probably just that they think there is shame in ending things. But viewing something as shameful is essentially a "moral" stance. So if they stopped thinking in terms of "morals", they could more easily see the clear path forward that would be good for both of them.