Tell him he's smothering you. Be straight up.
Iight so im really feeling like my boyfreind is obsessive over me....hes called me 19 times in the last hour geesh get a life! How can i tell him i need a little space between me and him...(nicely)?
Just tell him to dial it down a little, as he's getting too needy and clingy for your liking.And that you need your own space and more "me time" to be able to do your own thing and hang out with friends.
Just tell him, "I need some space. I feel like your too clingly" and he'll understand. Relationships are about trust. He should trust your space.
I think it is also important to know why does he think he needs to contact you constantly. Maybe that is a sign of insecurity.