my best friend's ALWAYS mad at me

Caitlin

my best friend is always mad at me about SOMETHING. and it's at the littlest things. like, i didn't tell her my grandma was in the hospital and she got mad at me, but didnt even ask about my grandma. excuse me if i don't text u because i'm visiting her... she also hogs my locker and uses it even though she has her own, and when i tried asking nicely and told her it wasn't working out with the whole "using my locker" thing, she got pissed and started ignoring me. she stuffed so many things in there i had to carry all my textbooks and binders around in my backpack all day, so i really wasn't trying to be over dramatic and mean to her. what's her deal? it's honestly so annoying and everytime i ask her if something's wrong she'll roll her eyes and says "nothing just go" like what's that supposed to mean?