cuz you didnt leave before the lights came on :P
NEWSFLASH: it was something u said.
Perhaps the 'nice' bit was an act to draw you under her demon veil....and only then would her true colours start to show.
she found out how boring goodness is so she wanted to walk on the wild side, she can feel the evil yeovil coming in like a breathe of fresh air,
She's a woman.
She succumbs to her 'feelings' which can cause violent mood swings.
These mood swings can be particularly violent if she's on her period.
Maybe she went over to "The Dark Side" lol
Balance, it is a bummer.