Sometimes writing is the only way to get out what I'm trying to say. For some reason words flow better when I'm writing than when I'm speaking. It's probably because I'm focused on my thoughts and not other things that can be a distraction.
Although not the best long-term strategy, using a mans favorite coping mechanism Compartmentalization might be your friend here. Focus on the thing you have to do. Right now that is being a dad and looking after your kids. Give them what you didn't get - and I don't mean stuff. I mean love, and the fact that you are present in their lives. Hold on to that with all you have.
I told you there are many layers that are compounding your problem right now. I told you to get professional help. What I was going to tell you before our call ended was that your wife needs help too. You've described some things to me that lead me to believe much of what complicates your issues are her fears and concerns related to hew own emotional baggage.
You reminded me you are a therapist. As a therapist, you have to know that making references to how well things are set up and the family would be OK if something happens sounds a lot like someone who is contemplating suicide.
I can hear the anguish in your voice. I know the feeling of being ripped in two and not knowing how to live through the pain. Our situations are different, and you are seeking a different outcome for yours that I did for mine. That doesn't mean the pain isn't very nearly the same and the thoughts and feelings don't run the same path.
I've heard how you could never leave your wife and kids, but yet that would be OK somehow if you died and didn't have to face the pain. I care a lot about you. I'm very concerned about you. I love you. Unfortunately, we (you, your wife, me) are not in a position that will allow me to be there to hold you and listen. To let you cry and yell and get it all out in the air. I want to be there. I'm afraid for you that you won't get help because you feel you won't get the answer you want to hear and that your professional pride won't let you admit to another professional that you need help.
Focus on what you have to do. Don't try to take it all in at once. That is overwhelming for anyone.
I'm sorry I can't be there for you.