birthdays = drama? what the...

So my birthday is coming up. Great. Gonna get crunk (cant believe i used that term). No biggie. Got a friend whos birthday is a day before mkine so we're having a nice double-party. i've had parties before theyre fun not a huge deal just like 10-15 friends and they're great. I have a dec number of friends who are girls... like more than dudes. I can thank ty for that. the thing is is that the girls are split into 2 groups. did i mention they all hate eachother? that can make hanging out difficult, but i deal. i'm "chill" as someone recently put it. so the way i want my party is that all of my friends come over, they can get over their hatred for one night. so now apparently ( i dont bother planning parties at my own house i just get the booze and ait for people to show up) some of my friends arent coming because of this hatred. how fucked up is that? how extremely selfish is that? i don't ask for alot. i really don't mind that they hate eachother, i never hang out with both groups at the same time anyway. all im asking for is one night where i can be with all my friends, but apparently a birthday party for me isnt about me at all, its about avoiding at all costs that group of girls that they hate. this night is not about them. i cant get over that these people cannot put aside their differences for one fucking night. i should just cancel the whole damn thing.