How to handle a jealous guy?

Ok so theres this boy name Tomas i've known for 4 years and hes jealous of everything I do. He isnt abusive or anything hes completely right minded. Its just that whenever im with anoter guy he says "do u love him, its ok if you do i cantc trol who u like and bla bla bla" I tell him not to be jealous but hes always following me around, callimg me. We go to diffrent schools and he says he tells his friends about me all the time as if we r exclusive (which we're not) and he always says he dreams about me snd when I dont talk to him he says he crys over it. Pleasee help its driving me insaneee