Well, he needs to be told he can be honest with his father about his feelings... He just validated his father's exit and he doens't even realize it.
How is your H mentioning he's looking at apartments STRESS FREE?
I would tell him to keep any commentary about an exit to himself. It's abusive to hold an exit over someone's head like that and he needs to hear that from you.
Tell him waving the "I might leave, I might not" over your head he may as well wave a knife at teh whole family and to knock it off... Make a point that you aren't being mean or silencing him but you have to protect the kids from this kind of abuse...
