Why did couples really stay together in the "good old days"?

I’ve been thinking about this question for years now and still can’t seem to come to a satisfying conclusion.

Part of me thinks it was because women were more oppressed and more likely to put up with men’s shit since they were dependent and didn’t want to face the stigma/struggle of being a divorcee.

The other part of me wonders if people really more patient with each other back then and less likely to “throw something away if it’s broken, just fix it” blah blah blah. Now, people think that if they break up or divorce their parther that they can find a replacement. Divorce is also more socially acceptable for both sexes.

What do you think?