What do you want to set a firm boundary on? Him meeting up w/the OW today? You have absolutely no control over this man. The more you try to set boundaries concerning the ow, the more he's going to go against them. He's not a child, but a grown man and he's going to do what he wants and when he wants. The only person you can control is yourself and how you react to his behavior. Keep this in mind...you do not want to sound like his mother.
As you can see, your H is being passive aggressive by not making you coffee. You will see a lot of this along the way, but I wouldn't let him know that you've noticed it unless it gets really out of hand.
I had to chuckle about the divorce papers and where he left them. Again, passive aggressive behavior. I wouldn't say anything to him about them. The less you say, the better. If he wants you to know about them, he'll raise the issue w/you.
I think your problem is fear. You want to see their relationship fail because you think he'll return to you. There are times when the relationship will end, but that doesn't necessarily mean he'll return to the marriage. Many of them go off and find someone else to be involved with. If he wasn't the ow he's w/now, he would have found someone else. The ow is nothing more than a band aid to his pain. His feelings for her do not run as deep as they did for you. She's just there to stroke his ego and help spend his money doing fun things, etc. You've got to understand that his journey is not about you...but about him and he has to go back and relive his past in order to return to the present as a mature and more settled man.
As we all say around here, when the bomb drops, they are already 18-24 months ahead of us in detachment and the "old" marriage is dead, kaput. We are blindsided too little, too late to do anything to correct the issues in the "old" marriage, so we scramble around, pretzel ourselves, trying to convince them that home is where they want to be and, of course, w/us...but they are too far down in the rabbit hole to listen to us until many years later and sometimes, it's too late because we've already moved on and created new lives for ourselves. Right now, I think you are dealing w/fear of the unknown and what to expect...am I wrong on that assumption?
I would go ahead and take son out to dinner and advise your h where you and your son will be and if he would like to join you, he can meet up w/you there either for dinner or for the dessert.
Please, try to remember that you can't control or fix him. You can only control yourself and be there as the mature, responsible parent to your son.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
