NLW I just got caught up on your current thread. I may not agree with everyone else but really I don't think it was that bad. I hate that you feel so bad. I DO respect DB. But sometimes, it is contradictory to standing up for yourself. That is what you did. You took out your anger( a little of it) right exactly on one of the people responsible. I will be the first to say DB can and does work. However, you cannot have a relationship with 3 people in it. So as she is the 3rd person then by default she also has blame in this. Perhaps, you didn't choose the best place and time but it's okay. I am fairly certain from what you describe that you did not make a huge scene and that most people had no idea what was going on. Also, by not acknowledging this entire situation for all this time you have not given your H any boundaries whatsoever. In addition, no real consequences. He is finally starting to get an inkling.
It is way past time for you to enforce boundaries. If he wants to do something with the kids he needs to ask you first then with your permission he can ask them. Just like anyone else would. He also needs to do it in advance, and be honest if OW will be there.
If he comes to pick them up, he doesn't come in.
He knocks at the door just like anyone else that doesn't live there. Frankly you are right, he did indeed abandon them. Regardless of your feelings towards him still you need to remember this is NOT the same person you know and love. This is some other being entirely.

If you have to deal with your anger do it productively. Meaning, take the steps you need with the custody agreement if for no other reason than your H SHOULD be monetarily supporting the children. I see that for some reason you are resistant to the idea. Maybe it would make it too real? I dunno. Having the agreement doesn't change anything really except that some of your boundaries are then a real thing in black and white. They are also enforceable by law.

I agree too that you cannot insulate your children. It is a very fine line to walk. However, do NOT under any circumstances lie for him or try to cover up what is going on. If you do this it will only be harder on them later. It seems like they have a pretty good handle on what is going on. I would take them to IC anyway. Surely, there are alternatives out there that would be positive. Maybe even go with them.

Last but not least, try to let your guilt go. You did not do this. You did not bring this situation about. You might have contributed to his "reasons" for wanting to. Ultimately, the choice was his. The fall out is his.

For me, the first time my H left, I felt so worthless and ashamed. Like everyone was saying, "Look at her! Her husband left. She can't keep her man!" Really. This is what I felt. The shame was almost unbearable. It took a very, very, very, long time to quit blaming myself and actually see it was H fault and not my own.

As Michelle said ride out the emotions, and be kind to yourself. What you are feeling is normal! Everyone goes through it. You will cycle repeatedly. You will want to launch yourself at his head and tear his eyes out. You will have days where you feel everything is lost and you cry all day. Other days you will feel okay. It is all part of the process. It IS a trauma and as such you will go through the same emotions.

I hope you find peace. (((()))))