My boyfriend (29) wants to take a trip alone with his female best friend (29).

Hi everyone, I really need some guidance here, so I would appreciate a quick response. My boyfriend has a female friend in the US, and he’s scheduled a trip there with his family. However, he also plans to spend an additional 5-6 days alone with this friend, exploring new places and sharing accommodations. I can't shake off my feelings of possessiveness and find this whole situation unnecessary, especially since we’re in a committed relationship. Is it normal for me to feel this way? Or am I overreacting? I do trust my boyfriend, but I’m confused about why they need to go on this trip together without anyone else. Does this seem like a big deal only to me? While I trust him, the idea of them sharing a bed and experiencing intimacy feels unwarranted. I’d really like to hear your thoughts on this. Thank you!