Your last statement is spot on, of course, because back in the old days, you either had your wedding ceremony or just say "we're married" and that was it.
That hasn't been true for a long time. Marriage was originally a transfer of property (the bride) from the father of the bride to the groom, but it's always been about a societal/legal recognition of a relationship. There might not have been a government contract, but that didn't matter because wives were the property of their husbands and there was no divorce (or if there was, the wife was left destitute). Yay for the good old days!
Yes, destitution (and worse, depriving the women of their children) is what can result when women have no protection by marriage laws.
I'm not comprehending what you mean by it being about societal or legal recognition of a relationship, but it has definitely included at least some government-enforced protections for women for thousands of years now.
There's some in the Mosaic laws, for example, around ~3400 years old. They are very limited in scope, so it was still a pretty bad situation for women, but even "back in the old days" it was far more than just saying "we're married" and "now we're not!". Sure, you didn't have to have a big ceremony, but governmental laws of protection did kick in (when properly enforced).
Instead of the right of divorcing the man, the rights of the women that are protected by the Mosiac laws more have to do with the right to make sure that the man continued to provide for her quality of life (including her right to demand he continues having sex with her, so she can have children).
Which is pretty much the same thing @blueshogun is complaining of, just with a different spin on it. Instead of "government dividing your assets", it was "government forcing you to use your assets to provide for your wife". It's not something new, and, in my opinion, very important.
No government dividing your assets for you in case of a divorce, no need for legal incentives, none of that nonsense.
Yeah, except once again, that "nonsense" is the whole point of being married as opposed to just shacking up together.
If you want to be legally recognised as someone's spouse (with hospital visits, inheritance, custody rights, etc) then you get married, and yes, that's especially important in the case of gay marriage.
Hell, in lots of countries, there is the concept of a "de facto spouse" once you've been together a few years to give you exactly these kinds of rights, and yes, obligations.
In the USA, we call that "
Common-law marriage", and while not nation-wide, several states have that here. It's a good idea, though I remember reading about celebrities and wealthy individuals divorcing right before the time-limit is up, so the protections don't kick in. That's when I think it's important to let judges have the flexibility in deciding laws based on the unique circumstances, rather than forcing judges to rule based on top-down broad-stroke one-size-fit-all laws.
I also agree this "nonsense" is extremely important. Yes, it can be abused, but it also provides real protection to really vulnerable people in bad circumstances.