Do i try to get him back or let go?

Ohkay so this is about me and my ex. We were together for lets just say a long time. We had a major thing and i knoe we were in love. There is no doubt in my mind. But then he went away and i went a little crazy and my friends told me he was all over other girls. Including this one girl Amber that i’ve had a problem with for a while, even though were friends now. So i was so upset but my ex had started talking to me and telling me i didn’t need this. And truely i didn’t think i did either. So my ex and I got closer and closer and we were texting one night and he asked me out. I was like what do i do about Billy? He said to just forget about him. So when he got home i was about to tell him it was done but my best friend beat me to it. She told him that i had been all with John which wasn’t true but i hanging with him a lot. Billy loved me so much that he just broke down and started crying in front of everyone at the field. It was horrible. So i started crying, too. I was like what do i do? Because then Billy and John were about to fight because of me. They were really good friends then, too. I felt so bad. I told John sorry i cant do it and John left. Billy wouldn’t talk to me for about 45 mins and then he fianlly let me talk to him in private. I told him i was sorry and what was going on. He was like I believed you when everyone told me all that stuff about how you cheated on me. I said, I knoe, but… He was like, Exactly so i thought we had trust… I started to cry and he said, Baby what do you want to do because i truely want to be with you. I said, Baby, you know i love you. I want to be with you. He said Well what about John? I told him that John wasn’t the one that mattered to me. And that what mattered to me was him, because he was my world and so much more. Billy and i stayed together. But the next day i was a truely unfaithful girlfriend and was laying on Alec, being the slut that i was. That day i broke up with Billy and right after i did, I kissed Mikey, Alec, and Donny. I invited Billy to come hang out with us, and he came. But Mikey was all over me and Billy told Mikey he wasn’t the jelious type, but you could see it in Billy’s eyes(which are beautiful i might add). I felt like dying but went along with Mikey. After that day i got into a huge fight with my best friend Brittany because Mikey was her ex and they loved each other but me and Mikey were venting on each other, by being FWBs. It didn’t work though because i went back to Billy, and we did go out, but he broke up with me after like 2 weeks to get me back, then went out with Brittany. So I was pissed. Then Billy wanted me back and I said no because i started going out with Alec. I really dont knoe why though because Alec didn’t even have a slight chance next to Billy, I was just stupid. Billy wanted me back the whole time Alec and I went out, Billy and I hung out and texted a lot, too while Alec was in Montana, but when he came home he broke up with me because he said i had more feelings for Billy, which was true. While Alec and me were going out, Billy was the one to walk me home at 10pm even though it was so out of his way just to be with each other and say goodnight to me. When Alec and I broke up I thought everything would be fine, and Billy and I would go back out. But just like that Billy was over me. He would be liek your a skank and i hate you. But it didn’t matter because i am in love with him. For 5 months we didn’t talk at all and when school dances started, we began seeing each other, and everytime they played our song, we’d cry or get so upset. And just sit alone and ignore everyone. They play our songs a lot because they are good ones. Like There’s Nothing-Sean KIngston, Forever-Chris Brown, Stickwityou-PCD, I dont want to miss a thing-Aerosmith, and Fall for you-Secondhand Seranade. Now it’s about 9 months later and in October we had a thing and would just be friends that had something. Then w
do i let him go or keep holding on?