I'm assuming that most countries in the world, let's say in the 19th century, had some kind of divorce laws in which you could divorce in the case of abuse, or adultery? Was this typically very difficult to prove, domestic violence if it wasn't physical abuse, or proving adultery as a woman? Even if there was a proof of physical abuse, wouldn't it still be difficult to get a divorce due to the patriarchal belief system of the time?
I can speak to Europe c. 1500, since I just reviewed some of that history. Back in those days, the family unit was much more critical to a person’s survival than it is today, which I think many people don’t tend to appreciate. This was especially true for lower-class peasants who worked the land, who constituted around 90% of Europe’s population. Though there were opportunities in urban areas, most people lived in rural Europe and relied on their families for all aspects of their security - for healthcare if sick, for a home, for work/food, etc.. Most marriages at this time were negotiated/arranged between the fathers of the family, who were seen as the authority of the family unit. This negotiation included the contribution of both families to the new couple’s survival, including critical resources like land and dowries. Even though the family unit was organized with the father at the top, there were strict expectations for all family members to abide by. So, a husband couldn’t abuse his family (with a 16th century definition of abuse) or fail to provide for his family without social and legal repercussions. If a couple had disagreements, there was such a thing as legal separation. But, it often made life much harder for those involved, especially for the wives. So, many couples who came across problems tended to work them out themselves.