Stupid cunt basically sent her entire damned empire into a deep freeze killing untold numbers of people crops and animals.
Then had a big musical number about it.
Then cunt blocked her sister from getting married to a prince, who was presto chango retconned into being evil at the last second out of nowhere becuase MUH JUST MARRIED MAN JUST MET bullshit as a terrible subversion, and to make her being an evil stupid cunt less fucked up.
Oh and the TWU WUV BETWEEN SISTERS THING is gay as fuck. Which is why they are going full on tumblr dyke with her in the next movie.
By the by, a princess needs to get shacked up and start producing heirs and since that was the middle ages and she was apparently knocking on her early to mid twenties and frigid and gay and seriously emotionally fucked up...I think her family line would have ended right then and there if she had stayed on the throne.