Next, it's like what lbhofwaw said. In most cases, I don't believe it's real. WAS are so good at hiding how they really feel from us most of the time. They want us to see them as happy and doing well, I think it's mostly because they don't want us to see and know how bad they really feel 1. so we don't feel bad and 2. we can't go "told you so" and make them be wrong in their choice.
I know it's hard, but try to stay positive. You do have the kids for two days. Forget about you W as much as you can and enjoy the kids.