I get it. He felted trapped here. He was isolated. I became that reason for the feelings of being trapped and isolated and now those are no more... he if free and he is happy. With the extra free time with not working he is building stronger relationship with his parents.
If he were free and happy, you wouldn't get nasty texts/calls, and he wouldn't offer to repair things at your home. Those behaviors probably indicate feelings of anger and guilt, which he's directing towards you.
Once you drop the rope he'll have to sit with those negative feelings. Where will he direct his anger? Where will he direct his guilt? The longer you're zero-contact, the less he can blame them on you.
Doesn't he know you're willing to move? Assuming he believed you--talk is cheap and I think you said you accepted you goofed not planning to move with your son's graduation coming up when he'd sacrificed by commuting for years, although he goofed more mightily by not communicating and choosing to cheat, it's not a choice of long commute + you vs. short commute + ow. It's just a choice of you vs ow.
