Actually I collect and read a lot of old books too. And also more recent historical studies of the 19th and early 20th century U.S. Certainly it wasn't just a sea of miserable marriages. But there were plenty of people for whom the overwhelming social and legal pressure to get married and stay that way "til death do us part" left them stuck in misery -- either unmarried or married. More ordinarily, people just didn't expect anything out of marriage except some economic and physical security, which probably a solid majority of them got. People want more from life now, and I think that's a good thing.
"Actually I collect and read a lot of old books too. And also more recent historical studies of the 19th and early 20th century U.S. Certainly it wasn't just a sea of miserable marriages."
You can try what I do now, I mostly quit reading non-military, American history books written since the late 50s.(mostly)
I have a library full of leftist books written by college professors, especially women that portray a dark sinister past, where women were nothing but chattel, or slaves.
In recent years main stream scholars have started fighting back, now you can find many books that are written without an agenda.
I come from an interesting family, on my dads side they are less than thirty years away from celebrating their 400th anniversary here. On my mothers side they never had any money and very little research has been done on them, but they have been here for over 200 years at least.
There is a lot of history in my family and much hardship, but I never picked up even a hint of self pity.
My mom's side have been hardscrabble Scotch-Irish Southerners that migrated to California as they picked cotton and fruit.
I never met any one in that family, or heard any history that sounded anything less than happy and proud.
My grandfather rode a horse drunk into a church to propose to my grand mother, but in marriage he is described as a very quiet, strong figure, that was a deacon in the Baptist church.
My grandmother is described as a somewhat dangerous, violent Indian, that while tough on every one else, loved her quiet, soft spoken husband very much.
Even when she shot a hole in the ceiling to break up my uncles, everyone was only amused by it, sadly at her age they managed to take the gun away from her for good, so that she was forced to sleep with a hatchet instead.
Since childhood I have sought out the stories of old people, usually women because they are more willing to talk, that means I have talked to many people born in the past from reconstruction to the Geronimo days, to the Rough Riders and the great depression.
I didn't find sad, passive women of limited options that had to marry a man to eat, or that couldn't leave a bad husband because she would be damaged goods, or starve.
If you want women in sad circumstances, that seem desperate and feel hopeless, at the mercy of the world, then look around today, and the surveys I've seen reflect that.