The way I look at it is this. Since we have children together, how do I want that to go? Will be "punishing him" or "teaching him a lesson" do anything to help a co-parenting R with my H? Nope. He's in my life forever. How would I like that to go. When I think of my kids, its much easier to be nice to him and not worry what it's "condoning". One of us needs to be an adult.

Just like MWD says, one person can effect change.

M: 9 yrs
T: 13 yrs
H:34 Me:35, S4, D2, S 7 months
Dday 11/12-PA & multiple PAs
Dbing 12/12
S 1/13
7/13 H moved back in basement.
8/13 #3 born
10/13 still cheating
10/13 He moves across country, I file for D