One of the main issues in our M was that my H felt unapprecaited and abandoned. We also fought a lot and I had a short fuse. His needs were NOT met by me and OW has done a great job at meeting them.
So if I wait to address the distance issue until the affair ends, I might never get a chance, since that R is only getting stronger every day. In other words, if I just detach and go dim, then he will never see changes and get to believe that I can meet his needs better than OW. His decisions to leave will be validated by my "doing more of the same" by keeping my distance.
From what I understood in this thread, Denver's W returned when she trusted him and came to believe he could meet her needs better than OM.
So my dilemma is how would I be able to show a stubborn, resolute H that our M can work by going dark and detaching, thus leaving OW to continue fulfilling his every need.
This ^^^^ is a very, very tough (and very, very COMMON) question. It's a valid concern, and it goes to the whole core of what MWD teaches about "pursuit." But the sad fact is, that while he is emotionally infatuated (and perhaps now even thinks he's genuinely in love with) his OW, he's not going to be able to "see" your changes even if he were in front of you daily.
"Don't pursue" is VERY counter-intuitive, but it goes to the core of effectively DBing. The only advice I would have for you is to see if you can look for other ways for your husband to see that you are a changed woman in terms of being more appreciative generally. But if you try to directly show this to HIM (say, by way of Words of Affirmation or other compliments), he's only going to pull further away, in my opinion.
Do you think he has EVER -- in the past 20 months -- genuinely felt like he was in any real danger of LOSING YOU, emotionally?