What forward said is spot on. The OW is in the picture. The kids have already interacted with her. Time to let go and let God. Time to really separate you from the R that XH has with the kids. Time for Trusting to really focus on trusting's happiness.
As for the button pushing..If you know it is coming why do you allow it. Maybe you need to get to a place where you really (and I mean really) limit the contact with your XH. Almost to the point of text only.
Having said this I do understand how difficult it is when children are involved. It is sooooo hard BUT it can be done.
God Bless, Eric
"The difficulties of Life are intended to make us BETTER,not bitter". "Fear is a prison, where you are the jailer. FREE YOURSELF!" "Life is usually all about how you handle Plan B." - Jack3Beans