Advice on trip?

So my boyfriend planned a trip for me and him and now all of a sudden his friends want to go. Another couple. There’s already need alot of drama with me and my boyfriend and the friend said they don’t want to be around it. Our birthdays are 2 days apart and i don’t really want to spend my bday with them. I know he won’t talk to me most of the whole trip because he will be with his bestfriend and i don’t really talk to his girlfriend. I get a weird vibe my bf has a crush on his besties girl. That have been around each other for like 4/5 years so they’re all close and i will feel out of place. And all the boys will want to do is drink and i don’t want too. I thought this trip was just me and my boyfriend to get away and rekindle and he just sprung it on me. If i tell him how i feel i know he will get mad and feel some type of way. I do not know what to do. 24F, 22M, 22F, 22m. Any advice on what to tell him without getting mad?