Me 13F cannot get over this guy 14M who probably hates me.

Me (13 F) and him (14 M) had a very short lived unofficial "relationship". Also I'm aware I'm young, that doesn't matter. For context we met doing our school's musical, we also go to a 7-12 school. I was in 7th grade and he was in 9th, we met because he went through a bad breakup and didn't have any friends in the musical. Many kids (especially my age but some of his ex's friends) accused him of "grooming me" because of the gap in grade levels. We both liked each other and both denied it for months. One day he asked me if I liked him, I panicked and said no, he seemed really disappointed and I regretted that. His ex girlfriend started harassing me because of his somewhat obvious feelings toward me. On the last night of the musical we were hugging and holding hands and all that shit. Afterwards I hung out at his house with a group a few times. He started acting really different. Then when I asked him what was wrong he was really dismissive. His friend who was there told me he was acting different because "he was with his male friends" but apparently he used to really like me. He called me a leech and yelled at me to get away from him shortly after at a school event. I ran into him in public and he ran away when he saw me. He started vaping, which we used to try to convince this kid to stop doing. He started hanging with some people that we used to feel bad for because we thought they made bad decisions. He's a completely different person from the guy I loved and I want that version of him back. I don't know how to get over it. (Sorry for the rant, tysm for reading the whole thing)