View from the other side:

http://www.slate.com/articles/life/dear_prudence/2012/10

Q. No More Baby Talk: My ex-husband divorced me last year so he could marry his pregnant mistress. Much to everyone's surprise, our kids together adore their new baby brother. They love to go over to their father's house to play with the baby, and sometimes I feel like the bad guy because I'm unwilling to give up my custodial time with them so they can visit the baby. They talk about the baby all the time, even though I've told them talking about the baby hurts me. My 10-year-old son wants his little brother at his upcoming birthday party, even though my ex and I agreed to have separate birthday parties from now on. Hearing about my ex's new fabulous life is agonizing. I know it's crazy, but I feel like my kids are choosing their dad's new family over ours, too. I'm still reeling from the divorce. Sometimes I get short with my kids when they're talking about their brother. I am trying as hard as I can not to taint the relationship between my kids, their father, and their new brother. Is there any healthy constructive way I can tell them not to talk about the baby so much? I'm worried I'll blow up one day if I hear much more about the baby.

A: I had a neighbor in exactly this situation and I could only marvel at her confidence and generosity as she seamlessly brought the new sibling into her children's lives. That baby brother was often at their home and he attended all the important functions of her two kids. When I said something to her about how amazing she was, she said whatever the adults did, the children were all a family and she wanted them to feel that way about each other.

I doubted I could have been that magnanimous. So I understand your anger, grief, and pain. But it will benefit you in the long run of life if you can support your own children's embrace of their new sibling. To get through this I think you need a therapist to unload to, at the very least. Together, you can figure out strategies so that you can support this newly constructed family without feeling you are going out of your mind. If you have primary custody of your kids, because of your husband's perfidy you have become a single mother. That's a huge load to carry, so don't be so quick to limit your children's time at their father's. It's good for them, and for you, if he is stepping up and spending a lot of time with all his children.