Should i let him go? Please answer this i really need some advice?!?!?

Okay soo i like one of my homeboys manuel. Nd he would always tell me these MOST amzing sweet things ever nd i really liked the kid i still do nd he likes me too nd dis new girl comes nd she started goin out wit him then last friday me nd manuel went to one of my frinds party later around wen ppl started leavin me nd him madeout in the dark in the kitchen.weve been planning diss for a long time nd he wants to makeout wit me some more but im not shure(i want to) nd p.s him nd his girl alwayss argue