doubleAA, We ALL make tons of mistakes while DBing....but we're constantly working to stop making them, thats the real difference. Its not that your not ready, its just that you haven't gotten to the point where you can apply them more often than not.
Stop engaging in the relationship talk first off. Its the first thing you can do...it will accomplish many things. It will make her wonder...it will keep you from getting hurt or hurting yourself by not getting the answers you want to hear right now...it will allow her to relax more. When she asked you if anything was wrong I can assure you she was talking about at this very moment....not is anything wrong in general with your life...she knows about the other no need to rehash those things. She was fishing to see if you were ok with her being out all night I would think so thats why she wanted to know if anything was wrong.
I havent read through your whole sitch yet and I will, but just based on this post I have a feeling that your relationship has some control issues to it and she's wanting to know if your willing to give that up so she's going to push you and see if you'll react. The number one way to defeat that is to not react. Its a very simple 180....when she says is something wrong say no.
Im gonna read a bit more of your sitch and see what i've missed but from what I know right now you have a wonderful opportunity to turn this thing around but you have to stop shooting yourself in the foot.
I have one piece of advice that I hope you'll take....dont talk about your feelings...your relationship with her....why she won't "work" on your marriage....doing any of that right now is reinforcing the negative and thats the last thing you want.
Smile...be nice....read the book and if you've read the book read it again. I can see this working out for you, but not if you keep pushing.