You remind me of myself some years ago. Going over all the details, the history, combing through it, analyzing everything. What I can tell you is that it doesn't matter. The relationship is extremely unhealthy, and you cannot change him. You can only work on yourself. Staying with another very dysfunctional person can be a way of avoiding working on yourself, creating a situation for yourself where dysfunctional is the 'normal'. Then you can distract yourself by obsessing over the details and who was right, who was wrong, who was to blame, who is the abusive one, etc. None of it will matter in the end. All that matters is that this relationship is very unhealthy for you, you cannot fix it, and you need to work on your own self, which you cannot do in such an unhealthy relationship and environment. I can also tell you that one way or another, stay or go, you have emotional pain to face. There is no avoiding it. Accepting that is a huge thing. However one form of pain will help you grow and set you free. The other will not.