Most Helpful Guy
Not every insecure wuss, is a cheater.
Some guys are just big wobbly balls of insecurity, who live day to day terrified of the moment their girlfriends realize what pathetic pieces of sh*t they are, and leave them for the next guy they see.
Those guys try to keep that day at bay for as long as possible, by controlling every move the girlfriend makes. if she never sees another guy ever, as long as she lives... she can never leave him.
It sounds like your guy is like this - a great big insecure coward, who would like to lock you up in a cell without a phone, for as long as you live, just so he could feel a tiny bit more secure about you never leaving him.