Contempt is the word.
My ex did this.
Have to say, the funny part was I had never seen him treat anyone badly before in the 30 years that I knew him, but when he decided to leave me in a very, very, very shitty way his tactic was to try and make sure he came out of it smelling like roses.
I think in his mind, when he made that decision it was basically him or me.
Either he was going to tell the truth and be real in saying: he had a very happy marriage with a wife who adored and supported him and kids that loved him and that we had everything going for us and he had decided to leave it,
OR he was going to make it look like it wasn't his fault.
Like a little kid caught sneaking in the liquor cabinet.
We had a marriage that I would have ranked 10 out of 10 for happiness. No fights, got on great, laughter in the house, hot sex! You name it, and when he decided to go I think he just had absolutely no solid reason so he had to create one.
He told people behind my back lies about me and our life together.
He blamed me for all of it, painting himself as a saint for putting up with me.
He treated me with utter contempt. Utter fury and hatred the likes of which you would have thought I murdered someone.
It was like a switch tripped in his head and that was it.
He and I will always know the truth though!!! No matter what he says, I know the truth!