I really loved a guy for long but now he is saying that from after 7-8 months of our reationship he wants to b?

i really feel very lonely without him,he tells that not for mmy any reasons he just lost interest from me,he wanted to tell before but he could nt tell.he does nt have prob if i tell him to marry me.sometim he really tells he loves me bt mist of the times he tells just for sake of saying he tells all tht..I really cant think of myself wthout him..as he does nt have interest in me he does never call me by himself if i call then he does respond and if i ask "whr were u" n all such ques..he starts reacting very rudely...i really feel helpless..love him so much...cant decide whether i should leave him r bear lik this only..