YOYO is right...The OW are great manipulaters. He will not believe you. Mine didn't till he had to experience it his self when she thru my stuff out and also his stuff. So it ment something then because it was his. She is immature.
Be strong and start detaching. GAL for you and the girls. It is going to be rough but I know you can do it. Really support your girls...Try and be there anchor and strong for them because they will be for you.