Why am I attached to such a jerk?

Even after realizing I've been used for mostly and experiencing the worst hurt I've ever felt, why do I still miss him and wanna be with him? He seemed so perfect. He was older(23) and more experienced in everything, was so sweet and gentle.. Then I finally told him off after he wanted to have a 3some and he hasnt talked to me since and it's been 2 weeks :/