Having been in security most of my adult life, being married to a retired cop, and going through police academy myself, if she had grabbed me or one of my family members like that, well, one of us would most likely be in jail and the other in the hospital. If she had just come up and started her tirade, I would let her get it out and then let her know what is what, but to put her hands on you...
You handled it like a pro. In police jargon, verbal judo. (Do they still use that term?) Good for you and for her DH. Maybe she will learn.