best friend having sleepovers with my boyfriend ?

ok so my friend became friends with my boyfriend when we started dating and they apparently are homies now cuz they started working together and one night my friend asked if she could spend the night at his place and he said sure. i’m not the type to say no to that bc we aren’t the type to control each other but that shit bothers me, i trust him and stuff but it pisses me off for some reason. shld i let it go or what i need help