How can i be less insecure?

Honestly it's a control thing and your insecurity talking, how I got over feeling this way with my boyfriend is if you having fun your mind is less likely to be worried about what him and his friends are doing and also trust plays a big part in this. Just go out with your girls while he's out with his boys and have fun. Honestly everyone flirts verbally and non verbally so don't worry about other girls he's coming back to you unless he's messing with someone I don't think you need to worry and you should be able to talk about stuff like that. I mean I know you see attractive guys all the time but you wouldn't cross the line because you have a boyfriend, so just trust him to do the same unless he makes you have a reason to question him. Hope I helped.