It's such a tragedy when children are used as pawns and end up being the "casualty" of divorce. I've heard of this situation often where a couple has to "de-program" the children once they get home from visiting the ex. It's a difficult situation not only for the children, but for the new couple as well, as they try to navigate through these circumstances. In many cases, the ex brainwashes the children specifically about the new partner their ex has and this dramatically impacts the relationship.
Well, bottom line is, the mother and father of these children aren't going anywhere, so a lot of compromising and patience needs to take place between all parties that involve the upbringing of the kids. Afterall, when two ex's have an acrimonious relationship, it's the kids who suffer the most!