Boyfriend having friends that are girls

Looking for perspectives of people older than 21 and who aren't married, still feel free to give opinion! My bf and I long distance and I trust him sooo much. I know he is friends with many girls who I have met. He isn't a partied/drinker and all these girls are similar to him. The guys he lives with are typical guys with hooking up/drinking 24/7 etc so I totally get why he doesn't want to be around that plus girls understand his relationship while his "friends" have straight up said cheat on her (mind you this was in front of me). He's my first bf and I trust him with girls since I have known him awhile. He's been hanging out with them more doing hw and all. I don't want to miss out of him cheating on me but I don't want to blame him for doing nothing. How do I handle this? I want to trust him but it's more the girls I don't trust