Like I said earlier, if you feel the need to talk to your parents, I don't blame you. That is your choice, and you are certainly entitled to it. I just stated that you don't have to go into detail of your marital problems if you don't wish to.
One of the difficult parts I remember shortly after D-day, was how to be the strong, yet understanding father, while my world was blown apart. My kids were much younger than yours, so I handled them differently.
I don't want to go off on a long side story here, but I will anyway:
I had the best parents in the world...the are both deceased. I can tell you that today, and every day forward, I appreciate even more the relationship that they had. For that, I am one lucky bastard.
My mother passed away suddenly, 19 year before my father. I was the youngest of 3 children at the age of 24, and I can tell you that all three of us fell apart. My father, in his typical superhuman self, carried his three kids through that crisis. But I would still catch him crying occasionally...the first time in my life that I saw that.
But the one thing I knew, was that he would never look for another partner.
Fast forward 17 years past my mother's death. Due to his heavy involvement in AA(at this point, he was sober for 51 years, but he always wanted to help others), I somehow came to believe that he was emotionally involved with a member that he was helping. It seemed to bother him more about the problems that she was having(financially), and for whatever reason, I just had the belief that he just wanted some companionship in his later life.
I was wrong. He was just my typical father who saw the good in everyone, and was helping another person who was in need. There was no emotional attachment...at least in the way that I was thinking...and that was the end of that.
But the point I am getting to, is that it really bothered me. Way more than I ever thought. It was not my place to decide how my father lived, and if he was looking for company, then who the hell am I to say no? But I still couldn't come to grips with my thoughts. I was being selfish and confused....over something that was all in my mind.
So I can't imagine how your kids feel. They were blindsided as much...if not more...than you, if that is possible. Our parents are there to protect us---and we look up to them like no others in our lives. So how do they cope with this?
I only say this because you do seem to have as good a handle on everything as one could be, in your situation. Plus, on top of this, your wife in right on the edge, and seeing the destruction of the three most important people in her life, has got to be taking its toll.
I guess what I am suggesting is, to tread lightly. There is a whole world of unchecked emotion in your household. I wish you the best in how you see fit to handle it.
Sorry, friend.
Sorry for you, your kids, and your wife.