..
Re: how do u ..
Ok, here’s what you do. You seal their mouth shut with duck tape. Then you get the handcuffs…oh wait a minute…that would send the wrong message. 
You could punch them in the mouth…knock a few teeth out. That will impede their ability to speak for a while.
Hire a hit-man. The economy sucks…they could use an assignment.
More seriously,
You can be direct. Call them on their behavior. “You keep insisting to speak with me when I’m not ready. Bugging me is not going to speed up the process. I’ll get back to you when I’m ready…please respect my privacy and don’t harass me.”
Don’t respond to emails or phone calls. Ignore them. Eventually they’ll give up. The cold shoulder can hurt more than a direct rejection. Nobody likes being blown off.
Talk to them…get it over with. Clear up misunderstandings.
I wonder if it’s the guy you were formerly engaged to. If he persists…(and this can be hard when the other party feels they haven’t received closure)…have your parents call his house, if need be.
