If you get to a point where H is meeting your needs, and you are very confident that you are meeting his, *and* a sufficient amount of time has passed, you will not think about the affair, so at that point whether you forgive him or not will be irrelevant.
You will only continue to live in pain from it to the degree that your needs go unmet, and/or you are unable or he will not allow you to meet his.
HopefulStill is right on that using it as an "argument weapon" is a surefire way to torpedo your relationship going forward. It's very tempting to break that one out of the arsenal when you are angry but resist that at all costs.
Acc
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015