When a spouse cheats and and you don't have kids, you can make a clean break and wash your hands of them forever.
However, when they leave you for their mistress and you still have children together, you're left with the enormous emotional gymnastics of grieving the relationship while trying to keep it civil for the children. This can be exceedingly painful and awkward, and looks drastically different depending on what your relationship was like.
In theory, an ex who cheated on you should be grateful for any civility you extend towards them in co-parenting, but not all people have that level of perspective.
AITA for acting "too" friendly to my ex's wife? He cheated on me with her.
I used to be married to Jake, and he cheated on me with Melissa. We divorced over it and now he and she are married.
Jake and I have kids, a boy and a girl.
At the holidays, we agreed to have a family Christmas with Jake's family. He wanted me there for the kids sake, and I agreed, it would probably be good to have some normalcy.