Yes i can fully understand that ! Its not always easy to break up a family and home for many reasons. I would say the biggest reason is usually financial. For them to afford seperate houses (unless they are wealthy) may mean that the woman has to get a job (if she isnt working) which might not be possible with children. It is always hard to disrupt children without affecting their education or routine etc.
It is easier to put up and shut up until the split has less effect on t he children.