Look, IMO when the OM and your W sees "the family" as it really is, kids, laundry, cooking, cleaning, attending to the childrens needs and wants, it's the same. Different person maybe, but the same! I think you're wise not to allow your children to be caught in the middle of this. They don't need to be, however with that said, if she is intending to D you, they're going to meet him. Are you paranoid that they may actually like him? Well let me tell you, they will. He will try to show the best side of him and the kids will eat it up. There is nothing that you can do about it, but I'm telling you, the OM is not going to want to raise someone elses children. It may sound to him like a fairy tale right now, but when day to day life hits him square in the face, he is going to resent the children for being around. Harsh, I know, because your kids mean everything to you, but they are not HIS flesh and blood and they never will. He will never love your kids the way that you do so you see, no matter if your kids meet him or not, you are and will always be their father - no one will ever be able to take your place! Your W is in la-la-land. She thinks it will be a bed of roses and romance and wonderful times! When they get down to the everyday life, the hum drum of daily chores, homework, etc. that romance will go away! I'm with RBinBR - she may need to be shocked into making the decision that will be the best for the children. After all, it is about them, not you, not your W, not the OM. The children should come first! Again, I'm not saying that you're not putting the kids first, but your W and the OM sure are not looking out for their best interest!