I feel like I'm having a breakdown but at least I didn't cry in front of him.
Sounds like you are doing exactly like you should. Do whatever you have to do to hold in your emotions around him. Then when you leave let them go...whether it's in the car, the basement or in a treehouse. Drive out to an empty country road and let it out there if you have to. But NEVER in front of him. You want to go dark on him emotionally. Believe me he will respect you very quickly.
As you can see staying cool and calm is causing him to probably panic more than you know. Sounds like he's sending you texts, but you didn't say what they involved. Continue to act detached, like you are calmly scolding a 7th grader to clean his room or he loses his XBox privleges. But don't raise your voice. Hopefully you will see him begin to emerge from this fog when he becomes the one to see what he's losing.
And keep repeating this to yourself..."I must be willing to lose this in order to save this."BS(me) 48
1 son 14 yrs old
Married 18 yrs, together 21 yrs
"You never know how strong you are until being strong is the only choice you have." ~ Bob Marley