is that if a couple does want to stay together in the current culture, they have to find ways to be together and spend time ensuring that there are overlaps in life

Wars and the pandemic are useful for this reason. People who used to think they can survive alone in this world have now got some sense in their knees. They are now finding someone to pair up with lol. I guess the thing is that population growth leads to the relationship chaos and people get choices and in choices they choose to be alone.