Busto, I wasn't judging you, just speaking from your W's perspective.
No one can go back and undo things. We all have things we would change if we could. But it does take a long time to come to terms with your spouse's affair. BF and I have had many convos on this subject. He can't change the past and I can't forget it.
I would agree with your plan to apologize for the EA when she brings it up for now. If she continues to throw it in your face then you'll need to talk about agreeing to leave the past where it is and move forward. It's the difference between forgiving and forgetting. I will never forget what BF did but I have agreed to move forward with him so that means I have agreed to leave his affair in the past and not continue to beat him up about it.
FWIW, I think it's good to apologize and ask for forgiveness. BF didn't do that directly for a long time and I was very angry and upset about this. In fact, it's one of the reasons that I still question our R and do not feel like we are reconciled. I'm not suggesting that you go melty man on your W, but do make sure to clearly ask for her forgiveness if/when she feels the time is right. Once. Then don't bring it up again.
Overall I think you're on the right path. Focus on you, GAL, quietly work on being the best Busto you can be.
If you love somebody, set them free. http://tinyurl.com/2empx2g