YA & NA Romance ♥ discussion

Hi, I'm a new member of your group. It looks great. I'm an avid YA/NA reader--I probably read at least 5 books per week. I have a question I'm hoping someone can help me with. I remember part of a story I read, and for the life of me, I can not remember the book title or too much else about it. I read so many books, they sometime bleed together in my mind :-) Anyway, I've tried Google, and searching through Amazon, but haven't had any luck. What I remember is this: the female lead hates the male lead, and he doesn't know why (I think I remember he is either in a band with her brother or one of her brother's friends). The reason she hates him is at some sort of gathering, they got together and I think he asked her to go home with him; she left him briefly, but when she came back to go, he was all over some other girl and I think left for the night with that girl. He doesn't remember any of it. I don't know why this story popped into my head, but it is now driving me crazy that I can't find the name of the book. Help, please!

I'm so sorry I don't know what book you're looking for! I hope you find it, it sounds interesting.