Frank, I dont even know what to say. I am sorry that you are going through this, that your children are going through it, too.
As a mother, I just cannot fathom purposefully damaging my child emotionally. I cannot imagine hurting them by belittling their father.
Every action I take, every word I say, is done with careful consideration of the impact it could have on my son and his relationship with his father - and he is 18!
How dare she ruin their innocent childhood like this.
Frank, please leave no stone unturned in trying to find a way to have her leave. She is causing untold damage to everyone's lives.
I am thinking of you, my friend and praying hard. Walk away, turn away, do not engage with her.