Should there still be so much anger here - why does she care at this point she's left and is in the situation that she chose.
What am I missing?
RGB80,
You're not missing anything. Clearly, you're the evilest, worstest son of a gun to ever walk the planet.
When the spew begins, just take a step back (figuratively) and validate. After a few minutes of spewing, signal to her that you need a few seconds to interject. Then, stick out your index finger and ask her to pull your finger. With any luck, she'll stomp off while still fuming, but you won't have to listen to it.