How should I feel ?

So I've been having problems with my boyfriend allowing his friend to bring 10+ girls to his house ( all at different times) just to fuck them. One of the girls even decided to give his friend head in front of my boyfriend !! & she being planing to pop up at my boyfriend crib when his friend & her aren't on good terms . He says I shouldn't be mad because they aren't there for him. So I dropped it because it isn't my house anyway. Yesterday I was at his house & his friend called & said his girl is coming to the house & made sure to say it out loud so I can hear so I won't get mad. Also my boyfriend kept putting the volume down on the phone but he kept denying it & said he never told his friend I was mad. Anyways the girls arrived & his friend wasn't there yet but he still opened the door for them & one of the girls made a comment & said " Ouu look at that haircut "and giving him compliments but I was upstairs the whole time . I told him about it and he said I shouldn't be mad because she talks to his friend also he doesn't say anything when boys compliment me & I tell them thank you. Anyways he dropped me home and left the girls in his house alone with just his mother because his friend wasn't there yet . Any thoughts on this ?