Please HELP me, i'm very devastated and ruined!?

My ex hv been extremely busy & stressed coping wth work & part-time degree, might be due to tis reason tat he initated our breakup abt a year ago, he used to shower me with love. But ever since his study started, he said he doesn't hv time for me. For 1/2 a year, he hv not sms or even call me up. But aft his exams over, his sch holiday came in July, he invited me for a trip oversea, can anyone tell me if a guy really loves u, will he only contact you when he is free? I'm still puzzled, tru out the trip..i can tell the feelings he had for me was totally different frm what we used to hv.. we "did it" during our trip, he made me feels he jus wanna satisfied himself. Aft our trip back, he totally avoiding me, jus like he's "back to busy mode".. i know cannot buy love, but it true feeling i had for him, why did he wanna hurt me badly and left me so devastated till now if he doesn't luv me anymore?! Am i being too blinded by love, or he's jus simply making use of me? Help me, i'm trapped