"Stay for the children" sounds like a simple moral position.
It is not a simple relationship decision.
Children matter enormously. So does the environment in which they are growing up.
The useful question is not only:
"Will separation hurt the children?"
Change can be painful.
The fuller question is:
"What are the children currently living inside, and what would each realistic future ask them to live inside?"
That keeps the focus on the actual family rather than on a slogan.