S16 seeing a psychologist is not something you must tell H. He has made it clear that you are to have sole custody. You are obligated to share matters of life and limb, the rest is up to you.
In this situation, I would specifically ask S16 if he wants Dad to know he is seeing and talking to someone. I suspect S16 will want his privacy. Assure him that you will honour his request, and if you ever have to explain S16’s sessions to Dad ensure you tell S16 of it and why it was needed.
This will help with S16’s rising feelings of indifference. That numb feeling is a healthy step along the path of healing. It is great to see you and son talking openly about it and other things. Assure him this numbness is temporary, as feelings are, and that it is completely normal and actually a good sign.
I am sure the other two boys are similarly feeling numb and somewhat lost. That is pretty normal since this is a never been lived through situation for them and you.
Dad will have little clue as to how the children are feeling towards him. A person in crisis is living a fantasy narrative and people are seldom the villain in their own stories. Let them tell you anything they want too. You need not have all the answers as oftentimes it is just they need someone to hear them.
Your double feeling. That wanting to let go and wanting to be there for H. I hear you.
There is a peace within the storm. Those two views are not as exclusive as one first sees them to be. You can do both. Consider what you can control. H is making his decisions and is running pretty hard and fast. You can care for him and let go.
Do not demonize him to the kids. Do not gloss over things either. Be open and honest (age appropriate of course). He is their Dad, and he is hurting. It is completely fine for you and them to let go, and in truth is needed. It is needed for you guys and for H.
H is driven to get space and distance from those that care, for he cannot handle that right now. MLC is such a messy emotional torment. The best way for you to be there for him is to not block his path. Let him go to make his decisions and gain the experience and consequences of those. Hopefully he will grow up, learn, and heal.
Letting go will allow you and the boys to heal as well. H’s path and pain is not, and has never been, about you nor the boys. You didn’t break him, therefore you cannot fix him. That lesson is age appropriate for all your sons. It helps with their indifference and to find acceptance of their feelings.
You are doing really well my friend.
D
Feelings are fleeting. Be better, not bitter. Love the person, forgive the sin.