This Story is bittersweet !?

I'm 14 and I'm in the 8th grade. I met my boyfriend when I was in 7th grade .We didnt get together until the last 1 1/2 month of tge school year. I thought he was the perfect boy! He told me how pretty I looked everyday,we studied together, after each period we would hug or talk . I even met his mom and spent time with him over his grandmother we had such an awesome time ! Things were going great but we did disagree alot . We dated for two months which ended because me and a previous boyfriend of mine kissed . I didnt intend for that to happen but it did and the boy is his cousin! I felt so bad ! He found out and my intentions were to tell him but how could I ? He was so mad that I didnt tell him and that he found out from the boy ! I really cared for him I had deep feelings for him and now I find it hard to move on ! I want a second chance but he finds that hard to give. How can I get him to give me another chance or should I just move on ? Plzz Help ! Thank Youu ! :)):