I need some help with a reallllly bad break up...?

im 15.me and my boyfriend were dating for 4 months and he cheated on me with a girl who i honestly think it a slut and so does everybody else. he told me earlier that day that he loves me but then he goes out on a date with her and i find out. he came to my house and i was yelling and stuff and he told me he just doesn't have those feelings for me anymore and that he was sorry. i yelled some more then started bawling and ran to my best friend. its been two days and hes already dating the tramp. i mean he wants me to be his friend but im not sure if i can cause i stilllovee him sooooo much even thou he put me throu alot . and he keeps telling me hes so sorry for how he handled that. see normally when i wanna get ovr a guy i find a new one to flirt with but i dont like anyone else i only love him and i just dont kno how to get over him. i cant think of anything.