why do people selfish???

i think im a lil bit frustrated right now when im writing this. its not like im selfish or what not but i cant hold it anymore. i feel like i needed some place for letting it out so that i'll feel a lil more okay. sorry for having this bad feelings but really, i dont like it at all!! so please act like you dont know me coz i dont wanna know you. but how can i escape from this when we're living under the same roof and go to the same college?? i know it's so wrong to dislike you deep in my heart but acting like i'm okay. damn!!! i hate myself for having such feeling!!!!!!!!!