I cheated on my boyfriend help?

Im in highschool going into 11th grade next year. Right now I have finals and last Friday a ton of kids from highschool came to Sams party to have some fun before testing starts. I rode there with my friend Christine and her older sister Hailey who is going to be a senior next year, and Haileys boyfriend Jeff. I did not go with my boyfriend Adam because he likes to ride with his friends all the time and I feel like he has been ignoring me a lot lately and thought he was going to break up with me soon. He said he was going to Sams party but I just hung out with a few friends until he texted me back saying where he was at Sams place cause its huge. Christine is more chatty then I am and has a lot more friends so she left me after a bit, but then Jeff came over and we started talking and he is really hot and a senior so I was starting to like him. It was a nice night, so we wanted to go for a walk and we kissed!!it was really passionate, but I felt really guilty afterwards because Hailey has always been so nice to me and I have known her since the 5th grade. I don't think that Jeff felt bad though because he told me that he was going to break up with Hailey anyway this year when he goes to college. But still I don't know what to do. I stupidly told Christine after the party and she doesn't want to be my friend anymore because her sister and her are bestfriends and I havent talked to her in a few days. I don't know if Hailey knows yet or if Jeff even told her. I also feel bad for cheating on my boyfriend who is not breaking up with me because I found him during Sams party and he told me that he loved me like he does and said that he is tierd because his sister just had a baby and it cries alot which I forgot about. I dont even want to be with Adam anymore I want to be with Jeff I think that I love him because we like the same books, tv shows, he is really smart and has goals, and really hot. What do I do?