Sorry you find yourself here. You sound like you have a good start with DB coach and Sandis advice and there really is not much more to add.
I am not an expert with A but know of 2 EA's that W has had. One with an old school BF and one more recently with a married man. Not sure if either went to PA or are still going on.
If I were you I would stop and take a breath. You don't need to rush anything re confrontation or anything like that until you have your life in a place where you are prepared to accept S or D....unless that is what you want. In my opinion from reading these and other I doubt confronting her will give her the wake up call you are expecting....more likely the opposite....but like I said I am not an expert.
Also W will probably not play an active role in saving the M until the A ends...so all the work has to come from you.
What do you think she is getting from OM that you don't give W. Sandi mentioned there is usually a reason i.e. emotional needs being unmet...this was certainly the case in my M!
In he meantime I would try take the focus of the A (easier said than done). That means no snooping, don't mention OM(except here), GAL, work-out, run for miles or whatever it takes to put OM out of your mind...FWIW I chose working out at the gym, horse riding, running etc.. you get the drift...anything that clears your head, helps your PMA and takes the focus off your sitch. ...GAL as others advised...and get out of your comfort zone..do something different.
Also on the 180's she may give you the too little too late talk so be prepared for this. This is script for the WAW and remember you are doing it to for you because you need to change...these are life changes and not tactics to win her back. Don't fall into the trap of keep changing to get a reaction from W. She needs to see consistent changes for months or even years.
I would also hold off R talk unless she initiates it, avoid all pressure, be upbeat at all times, read DR again and again to learn the techniques and also 5 love languages if you haven't already.
