Not sure how much advice I can offer on that one. You can't make your xw take their feelings into account...it is just beyond me that she doesn't.
I think if you just keep letting them know that you are "happy" then it will help. You may not be happy with how the situation has turned out, but in you still have things to be thankful for and they need to know that.
I really do think a lot of this is guilt on their part. If they should welcome this new guy into their lives they may feel like you will think they love you less. You have to let them know that is not the case. You can't control your xw or how she chooses to deal with things....so just keep loving those kids to pieces and listening to them when they need to talk.
As for FB...search for Kris Klm and you should find me.