You've pretty much got this exactly right... she's being nasty so that you will react so she can justify her actions. Try to think of it this way... She is probably much more confused, scared, and hurting than you are about this situation. She likely questions everything she does that she knows brings pain to you, and to herself. If you react badly, it DOES help her justify that what she's running from is you, and that it's the best thing for her to do.
You are actually in a position of empathy, because you do know the pain, and you do know the confusion. Difference is, you have no control over the source of the pain and confusion, so you can't do anything about it, except leave it alone and empathize.
You ARE living a nightmare. We all are or have. None of us signed up for this when we got married. It's not fun, but it's possible to wake from it. For now, you have to get all your love and compassion from yourself, your friends, your kids, and here. You can do this.
Yes, you are a good person. If you weren't, you would not be here and you wouldn't care so much.
