None of these reasons require marriage. Not one.
A committed, long-term relationship ticks every single one of these without a marriage contract, enforced by some third party like the state where you live.
I've been in such a relationship for 10+ years, and we've stopped learning useless dating info, share "tidbits" about our days, know each other better every day, wouldn't dream of ever ghosting each other, give and accept our mutual commitment as one of the highest forms of praise, care deeply about each other on a daily basis, prioritize each other, are *truly* daring (see below), and never go through storms alone.
Given the high divorce rate you cite and our own bad experiences with people "becoming" someone else as time goes on, it's not daring to risk second or third marriage. It could be seen as taking downright irresponsible and certainly unnecessary risks. Our relationships affect not just us but those around us too.
We were both up front about the non-negotiable never again status of marriage when we started dating.
What really takes guts is doing all this without some external force like the state and the church holding alimony and eternal damnation over our heads if we break our covenant.
Put another way, people are hell-bent (interesting word choice given the things I've said) on getting married because they want and depend on the false security the state and the church claim to provide to safeguard and preserve what usually turn out to be ill-considered and unsustainable unions.
Given the track record of government and religious organizations, I prefer to rely on myself and my partner, thanks. The fact that we remember all too well how unbelievably awful dating was and how incredibly fortunate we were to find each other keeps us present, faithful, etc.
Be a decent human being. Take responsibility for your own happiness. Be unflinching about your rejection of marriage. And leave yourself an out in the first few years that doesn't involve allowing someone else to put you through hell, bankrupting yourself, and/or being treated like a criminal just because the other person was dishonest about who they really are.
Marriage is a huge, completely unnecessary gamble to begin with. Doing it over and over, hoping for a better outcome is insane.
Bottom line: people get married because they're ignorant about what they're really getting themselves into, because they're afraid and won't stand up for themselves, and/or because they're lazy and won't do the work to avoid or accept the consequences of failure.
Or as a wise person once said, "Second marriage is the triumph of optimism over experience."
