I haven't read the entire situation, but I feel your pain. It's hard when you wish there was something that can be done, wish that one certain action would shake them, wish they consider the kids, etc. it's even harder when all attempts have been exhausted. I'm sure we all go through the same motions.
My walk away does not have another woman, but my first husband did. So I feel the pain there too. what I can say is do not think that your spouse forgot all your positives. Believe me they do. Stay strong. Not doing anything, is doing something. As odd as it sounds. My ex told me when he came back how much he missed my sense of humor. And all along I thought I was never on his mind.
I shake my head at WAS's bc we all made a commitment to stick this relationship out when we clearly can walk away as quickly as they did. I can't promise that they will come back, or that the marriage will be salvaged, but what I can say is you will be glad and proud of yourself that you chose to make the commitment to stick with your spouse. It shows character.