Don't even call him a boyfriend.. I referred to the OM preying on my home as "the creep" and didn't refer to it as calling our home but ias PREYING on it...
"Wife, I can hear him preying on our marriage. I won't tolerate our marriage disrespected that way in own home -- take it outside ... (no pause) Thank you. If he calls here again I am calling the police."
and stand thre until she does something... make NOISE to drive her out of the home if you have to...