"It shows you that the anger is coming from her, through her and until that is dealt with it will continue to be so." (Spirit)
That is absolutely true! WAS like to hold on to that anger, because what else do they have? My H was so angry with ME after HE left, and I was dumbfounded by it. I realized, though, that he was trying to validate to himself and I guess anyone else who would listen why he left. He wanted me to be awful and bitter and mean and a crazy b!tch! I just kept being sweet (or at least didn't engage in the arguing as much as he would have liked), and eventually, he had to let it go. It's hard to argue with/hate someone who gives you no reason.
Keep being sweet, Telemark. Or at least don't engage in the arguing too much. When she starts to push your buttons, tell her when she calms down and can communicate in a calm manner to let you know, and then end the current conversation. Eventually she'll learn she can't treat you like that. And eventually, she will let go of the anger (at least I hope so, for your good as well as for her own).