She would be perfectly happy if she never spoke or saw me again

Her ex is more important then anybody else. Most people don't continue talking to their ex, after they divorce them.

She'll also make you angry, as she has an anger problem. Almost anything will piss her off.

Calling her when her ex is at her house, will piss her off. And she wonders why I get mad when he calls her when I'm in her vehicle. Just returning the favor.