“Of course some couples do live together without marriage and wind up marrying happily. But most do not.”
Most people divorce including those that never lived together, so you only told half the truth when you said that, and half the truth is still a lie.
What is that supposed to mean? BTW it is well known that although (last figure I saw) roughly 50% of marriages end in divorce (and that may have changed), that includes second, third, fourth etc marriages. It is not that out of every couple who marry for the first time, half divorce. So, in order to accurately count divorces, accurate count of how many times people have married must also be done.
I can see you are clinging to your point of view that living together without marriage is benign or good. Or whatever. Cling away, but the facts belie your belief.