I do know what you're talking about DH. I've seen a number of people post here for whom this is their introduction to the world of poly. I'm glad it wasn't my experience. It's hard enough when things are changing and you're both on the same page as being internally non-monogamous. It must really feel like a blindside if you're not in the same place internally.
You're still hurting deeply from this, aren't you? A lot of what you write sounds very angry.
Everything will be ok in the end. If it's not ok it's not the end.