When I was very young I had a few jobs where I had to deal with the general population. (That was in the late 1970's)
I worked at Six Flags/Great Adventure in
NJ for 2 summers, and then delivered food trays in a hospital. I would calculate back then, about 1 in a few thousand people would be totally off their rocker and go wild on you. These folks take out all their pent up anger, roll it up into a fiery ball and blast YOU the worker (be it the kid operating the tilt-a-whirl or a Flight Attendant). They are everywhere, all over the world.
This woman was clearly nuts. I can only imagine how she must yell at the nurses and assistants at the plastic surgeon's office! She was half way along to looking like Michael Jackson (may he rest in peace).
Last, while United is often blasted for its mishaps and mistakes etc, here, I think United did the right thing and managed the situation as best as can be. Imagine if she lost it in flight!