Ughh whats the best way to... please help me? thanks..?

whats the best way to break up with a boyfriend? were on break now but as soon as we go to school he wil start a bunch of rumors about me and make my life hell.. agian he did it alot in eight grade we went out 12 timed this is the 13th...im sick of him cheating on me and hes to controlling. so whats the best way to break up with him? im 13 hes 15 if that helps.