You are grieving - the life you had, the relationship you thought you had, the future you expected to have.
Denial is normal as part of that and so is all the bargaining and guilt. You need to let yourself process those feelings rather than trying to force them away by trying to rewrite history or minimise what happened. He assaulted you and that cannot be undone now.
I don't read this as someone whose past traumas led her to "overreact" , what I see is them enabling you to react appropriately and take the right steps to put your daughter first. It gave you the power you needed to act.
The fact that the emotional challenges that have followed are tough for you is separate. Difficult emotions don't mean we did the wrong thing, they just mean we are a human in a difficult situation.
As mentioned up thread, I desperately feel like I've done something wrong.
I'd wager your sense of having done the wrong thing by responding appropriately to a violent assault is because the abuse you experienced growing up ingrained in you the belief that it was your fault, you deserved it and had to keep quiet about it.
Plus, if you can convince yourself this is all your fault and It wasn't really that bad then it a) makes you feel more in control and b) is a way of hiding from the reality of how your life has now changed.
Being abused and being traumatised has nothing to do with how well educated you are or your financial position. I'm sure you don't look at other abused women and think it's because they're stupid and deserved it, right? So why are you beating yourself up like this? It can happen to anyone from any walk of life. Some of us are more vulnerable but none of us is immune.
I don't think you would feel in control going back to the house where this happened. I get why you feel that way but it seems more of the denial. I think it would be harder to grieve and come to terms with the seriousness and permanence of this situation of you went back. Living in the space where it happened and the space where your broken dreams were originally formed - that's going to cause a lot of daily pain, no? But I do recognise the upheaval is another loss for you to process right now.
And unless your daughter was in a sound proof room when all this happened, you are kidding yourself if you think she was unaware. Even babies are affected by living in an environment where mum is being abused. Hearing violence through the wall as a child is terrifying. "Has mummy stopped screaming or crying because she's ok and he's stopped hurting her or is she dead? Am I next? "
I think a lot of posters, myself included, will have been terrified at reading a post by someone who sounds close to minimising the abuse they were subjected to and returning their child to that environment in the basis that "I overreacted and I don't believe it will happen again" (even though as you said yourself you never believed it would happen the first time - and no woman enters a relationship believing that man will one day abuse, assault, rape or murder her).
My mum never managed to leave and It destroyed all our lives. I ended up being abused as an adult too because it was all I knew.
When I left I missed my abuser, I missed my home, I missed the hope of him one day being nice to me, I missed the familiarity, I railed against the uncertainty and confusion and fear of not knowing what was going to happen next and all I had lost. I bargained and blamed myself. I felt guilty. I doubted myself.
A few weeks after leaving I even found myself thinking "well, I don't feel afraid all the time anymore, I obviously made a mistake leaving, I should go back". And then I heard myself and just thought WTF? Because I realised the only reason I wasn't scared was because I had left.
I know your situation is a bit different, but I'm sharing this as an example of how our brain can use denial and distancing in the early days of grieving. It can be harder to trust our judgement that we responded appropriately once we have the safety of time passing and the memory of how bad it was loses its rawness.
All of that passed. I survived. It got better. I did the Freedom Programme. I took up support and therapy. I reminded myself each time I wobbled or felt confused and overwhelmed that I needed to go forwards, not backwards. There is no amount of abuse that is fixable. Going back to it never erases it, no matter how much we wish we could. It's like trying to wash a burn out of a dress, you can't.
I hope you can get the support you need to stay gone. I do believe you can and will feel happy, secure and loved again even if the life you build is different to the one you imagined before. 