I need some advice

I have been dating this guy since I was 15, he has been my one and only boyfriend of three years. I love him a lot but I recently met this girl , who I can’t get off my mind and I hang out with her a lot now. I purposely pick up shifts to work with her. She is gay and everyone knows it. I feel bad for my boyfriend Bc he doesn’t know what’s going on but he doesn’t agree with same sex relationship, this is the first time I have ever been this attracted to a girl in my whole 18 years. I have always had thoughts but never got to carry them out Bc of my family, friends and boyfriends judgements . I just don’t know what to do. I think this girl is so fine and she is funny and kind and I think about her 24/7. I just don’t know what to do