The idea of what marriage is has changed drastically over the last fifty or so years.  For many centuries, marriage was a business contract between two families; love wasn't part of the equation.  Moreover, women were treated like property.  A woman had to submit to her husband.  It wasn't until the 1870s that abuse was considered a crime.  We didn't start seriously prosecuting it in the US until the 1970s.  Marital rape didn't exist as a crime until well into the 20th century.  A woman in the 1950s probably had little recourse when dealing with an abusive husband; now she has many more options.