doesnt knw to let him go are not?

im a reseverd gal wont talk with guy too much.i loved one guy very deeply he too,he only proposed me.we are childhood friends too,but they are differnt caste and religion,we shared everything but not beyond the limit,now he left me and went because of his family.But i cnt forget him, he too for sake our family only he did like this other than nothing else.he never left full heartedly.if i get marrriage with some one means i cnt lead my life with peacefull and my past life will disturb i cnt touch another guy.at the same time he too.because while we are in love he used to say ill marry u opposing my parents but now he left me,im a virgin gal but according to my mind not virgin i lived with him now he saying IM NOT APT FOR U.i begged him more times to consider me but the same replay only.im damn cheated.tell me one solution whether to forget him or to chase him?please give me one advice for me... NOTE: i cnt marry him at the same time i cnt marry anybody.if i marry someone means can i lead a happy?????/