Why did he just cut me off?

A few years ago, when I was in 7th grade, I met this guy in Spanish class, I liked him, and he seemed to like me back. He eventually confessed to me, and we started dating. At first it was great, we enjoyed each other's company and I used to sit on his lap and play with his hair when we had substitutes (lol) and it was just really nice. When we danced together it was like magic. When he put his hands on my waist it was like a warm blanket of safety and warmth. He always told me how much he loved me, and that I'm beautiful, and that he'd do anything to make me happy. Then he moved away. That's when he started treating me like his personal sex doll. He always asked me for boob pics, nudes, videos of me moaning his name, and like a fool I eventually caved in and gave him what he wanted. One day he asked me to deep throat a banana while moaning his name, and I was like "Hell no". So then he was like "I don't wanna talk to you now, just go". And a few months ago, he told me he needed space so I was like sure go ahead. And before I knew it, he cut me off completely. He blocked me and unfollowed me on instagram, and stopped responding to my texts and phone calls. I'm so sad and confused. He still treats all the other girls around him like normal. Why did he get sick of me and just leave me hanging? By the way, I'm not one of those insecure girls who relies on male validation. I'm pretty confident in myself, and I know my own worth. But at the same time I can't help but miss him :(