How do I finally move on from my first love?

HELLO! I’m currently 19. I still really care about my first love (and the only person I’ve ever dated). He gave me my first kiss. We were together for 4 months last year, and then he broke up with me in January. You see, when I met him, he was still crushing over his ex from the summer. And I guess that he dated me in order to forget about his girlfriend…making me a rebound. I’m ashamed to say that when we broke up, I was upset for months…I even got really depressed to the point where my parents suggested that I see a shrink…I lost weight because I wasn’t hungry, I couldn’t sleep…When we broke up he told me that he didn’t feel committed to me, and that he didn’t value me as much as he should have…He also said that he was still letting his ex get to him. He told me in so many words that when we were alone and together (like hanging out) that it really didn’t mean anything to him. Well, 6 months later, we still talk on the phone at least once a month or text once a month (mostly from his part). One time, I even told him about my problem after he broke up with me. He just said, “Hmm”. Can anyone tell me why he still calls me? Everytime we talk, it hurts. How do I get over this guy and move on with my life? Should I stop talking to him altogether or what? I can’t get over the fact that he was a really good friend to me before and not just a boyfriend.