I don't blame you. But blame him more. Does she know you see his FB page? I am sure she does some of this out of spite for sure. In her mind they are a perfect little family. Its just a matter of time before she realizes what has happened.
I am sorry you saw that. I feel the same way when I see someone else at exh's or hear that he tells people how happy he is.
Blech!
Me: 46 FWS: 36 Married and Divorced 4/07, Pregnant 7/07,False R 7/07 Baby Girl born 3/08 Kicked him out because OW: 7/08 5/10 He realized what he had and lost. Moved home! REMARRIED 3/14/11!!