We know many happily married couples who didn’t shack up before marriage.
Conversely we know many unhappily married or divorced couples who did.
I don’t think the young people consider marriage as their goal. Rather playing house seems to be the idea. Room mates with benifits says it too.
Most young girls are under the false hope the ‘arrangement’ will one day lead to marriage. Even if they don’t think so the day does come where she always starts feeling used as she looks to the future.
I worked with a gal who lived with a man for 5 yrs and she began feeling like nothing more than a kept women. He owned everything and she didn’t have any ‘security’ if something happened to him.