My parents often said that they stayed together for us kids. I got tired of hearing it, and at one point told them to stop blaming their children for their mistakes.
When I left my ex husband, my parents were less than pleased. Several years later I met my now husband. After several years we decided to get married. The day before our wedding, my mom told me that she had hoped that my ex and I would get back together for our son. I was shocked, and offended. Up until that moment the only thing I had really said about my ex was that we had problems that we could not work past. I decided to tell my mom why I had divorced my ex. My ex had a severe aversion to monogamy, and had cheated on me throughout our 10+ year relationship.
My ultra conservative mother was appalled. Up until then, she had sent my ex birthday cards and gifts, Christmas gifts, and had basically been treating him like the much loved soon in law (that I had left, and didn't 5 years fighting in a contentious divorce). Needless to say, he was no longer the perfect SIL that they had hoped I would reconsider divorcing.
I cannot even begin to imagine staying with him for our son. I would die for my children, but there wasn't a chance that I would even consider getting back together with my ex. If Hades had frozen over, I'd have gone skiing. .
Staying together for the kids may work for some people, but generally speaking it forces the children to grow up trapped in their parents toxic marriage. Sadly, it will likely affect their children's concept of what a healthy relationship looks like.
Better than a thousand hollow words, is one word that brings peace. ~Buddha~