Pandora passed away at 16 leaving her mother compleatly crushed.
That's where our story starts: In the highest pick of the Forbiden Moutain, and the only with some grass and a living tree. Everything died with Pandora except that tree. And sending the frost, Maleficent was carefull enough to keept it alive so her daughter could always see there was something to remind her home. And beneath that tree lies the body of Pandora.
Maleficent noticed that a violet is growing near Pandora's grave and she goes every single morning, beneath storm, sun, rain or snow, sprinkle that simple flower with her bitter tears.
She's not evil, she turned evil, seeking revenge, brokenhearted...