My point is that if it was along the lines of a 'chuckle under the chin' as you put it, it wouldn't have been followed by 'you're a bad mother.' Would you honestly say something like that as a joke? I get direct with people, but direct doesn't have to mean physical or even insulting. I wouldn't make excuses for poor behavior. She's an adult, and regardless of where she's from, she should know better. I grew up around aggression. My own mother was very abusive, her mother as well. The majority of families I knew believed in 'spare the rod and spoil the child.' Meanwhile, I'm intelligent, empathetic, and I have a mind of my own. I choose not to get physical with people because it's not right, period.
As for the last point, I don't mind saying I grew up in a third world country. How does 'third world' imply anything other than less progressed/developed? It's not an insult to say it's a less advanced nation. In fact, that is one of the few things I remember fondly about it. It allowed for a more laid back lifestyle.