Sorry you are going through this devastating pain. I have a small suggestion, which might sound odd...
Maybe it would help a little to "own" part of the affair yourself. Yes, her actions are wholly her responsibility. But, you are responsible for 50% of the problems that led to her contemplating those actions. I'm not saying that this justifies her actions. But, perhaps thinking of it this way might make you feel less of a victim.
As to your wife bringing up old pain you caused her, perhaps she never felt heard about it. I'm sure you can empathsize with the pain and frustration of not having your pain heard. Maybe you could ask her for a conversation in which you both just talk about you pain, past and present, without placing blame, just seeking understanding.
I think the idea of taking a break is a good idea. You are, understandably, in a very traumatized place right now. Take care of yourself and give it some time before you make decisions.
