hmmm tough one. Would telling his wife actually result in him stopping his attempts to contact you? Is there a risk it would escalate (you said you moved)?

Did you try a straight up "i'm not talking to you again" and hanging up; followed by hanging up without saying anything as soon as you hear his voice on subsequent calls?

If it comes to it, you could always temp route your current cell thru an answering service as you transition to a new number. A pain in the youknowwhat for sure, but doable if needed.