I turned 13 in 1960.  I remember well that time and the rules.  I remember the women of my mother's (and your mother's) generation.  My mom was a bit different (it's a long story), but your mom could have been by Girl Scout troop leader, or my teacher, or the mom of one of my friends.
Many of those women, later, could not put up with my feminism, because it was too threatening.  I imagine that your mom simply could not face the reality of what happened to you and her inability to protect you.  It IS very sad.  I am truly, truly sorry for what happened, and I'm not trying to minimize what happened.   It's just that, as I've gotten older, I understand more than ever before what a job society had done on women -- to their detriment and that of their children, ie of all of us.  If moms had been treated like people, they would have done a much better job protecting their children.