I never say anything negative about my H. When my kids say something negative, I always rephase it and try to say something positive.
As far as the OW goes though. I make it clear to my kids that is wrong and your father is sick. I let them know that he is not using his best judgement right now and needs us to show him the right way/path in life.
Don't get me wrong, I have made mistakes and sometimes my kids will see my dislike of his actions and behaviors, but for the most part I try to do this.
If I cannot find anything good to say, I say nothing.
Everyday I remind my kids that he loves them. Sometimes they doubt this because he is so self-centered and selfish. Especially when he spends more time with the OW's child then his own children. Or when he forgets to follow through on a promise.
Me: 45 H: 43 Married: 19 years Dated 05 years Bomb: 11/06 OW - "I love her, but still want you as my friend"