Hi Seanna... I know its not a consolation, but affairs don't last long term... they have less than 1% success rate... Whatever your H's plans are they aren't going to reach the fruition he's hoping for.. he's goign to land flat on his face again and again until he learns what love an commitment is.. Right now he just thinks marriage is acting on romantic feelings while they last and running when the fade away...
That is a delusion and it will fail him eventually... affairs don't last long term... He will likley cheat on OW at some point, or she on him.. the stats are very clear on this...
I know it may not help, but its important to keep this in perspective is all... and the stats are clear on what the perspective should be...