Well, the easiest way to Simpson to not affect Edward is if she had never met him. I seem to recall that she had a botched abortion in Beijing which left her barren. Given the likelihood of mortality from a botched abortion, she could have just as easily have died. Then again, he had a penchant for affairs with divorcees, as his then-Mistress Thelma, Lady Furness, was the one who introduced him to Wallis. So we could have a similar scandal but without the fascism.