Well yeah, that would be tough. I know how hard it would be to cut it off so abruptly, and I'm not even sure if I could take my own advice, but I bet if you did just leave him be for awhile (ignore his calls, if you do happen to talk to him let him know you're doing just fine, etc), he might realize how much he actually cared for you and you never know, he might wisen up. I don't know if you'd ever want to get back together with him, but if you do stop the contact and act maturely, you both might actually mature and then grow back together at some point if you are right for each other. Who knows!