I understand where you are and I was at a point that was similar not long ago. I didn't plan on actively leaving my marriage or actively pursuing anything outside of M but I did wonder whether I could just mentally check out of the M which would create LDness as an after effect. Then, if H felt moved to do so - he could leave or ask me to do so but I just wasn't striving anymore. I decided that I just wasn't meant to be married or that I was a terminally "poor chooser" of men and that I should just give up. I understand that the nuances of your thoughts are a little different than mine.
In my case I think it was a way of giving myself mental rest and moreover permission to quit "doing" - quit reading, thinking, processing, strategizing, worrying, agonizing and all of that. Can you find a way to rest yourself without the escape fantasy? Can you tell Mr. W that you are tired? Can you spend some time with some girlfriends and take a rest from "men" - a girls weekend perhaps? Not to man bash but to lift up all that is great in women? Can you journal about your feelings and explore them without totally checking out of your M?
