How do i get over this? (first time falling for someone)?

hes just a ! but before all this he was saying how we wanted to have with me what the hell? shh i'm so angry! its all hard to explain basically he said he got in (snogged) with some girl on his birthday he knows that i liked him and he said he liked me! then i said my opinion on her that shes ugly and a bit of a slapper from what i'd heard and so was her cousin. I didn't think he'd care but he came back with 'i don't' care what you think' he likes her and there's nothing i can do about it! i'm going to cry! i never cry! i'm grounded so i can nit get my mind off it i can nit keep myself busy. What do i do to make myself better? i'm really upset!