That is a horrific story. I'd love to say that sort of thing was rare, but I can't - give men a system where women have no choice but to stay, and some of them will behave badly. Far too many.
That would be a good guide for what the misogynists are thinking: "I hate [thing] because it gives women the freedom to leave if I do something wrong."
I'm sorry your grandmother had to go that route and glad your mom broke the cycle.
I just hate that you have to say "MY mother married a man who NEVER laid a hand on ME, and she never would have allowed it. And she raised ME to think for myself, to demand respect, to expect it, as a minimum requirement for any relationship." Those conditions really should be the baseline for everyone's life. Hopefully we're making progress, but it's awfully slow.