The "hmmmmmmm" meant that I thought it was interesting to consider that the wayward spouse might not see the betrayed spouse's GAL improvements as sincere when they are coupled with a hardline stance. That -- although it happened serendipitously in your sitch -- that it might have been good for you NOT to know about the affair early on, so that your husband would see your self-improvement efforts in a more sincere light.
I still advocate an early and forceful approach to busting up affairs, for the same reason you have to "get the liquor out of the house" with an alcoholic, but I thought yours was something I hadn't thought of before.