How to deal with a mean friend? :(?

I'm not sure whether you're only ten or not, but I'm 14 so I have a little more experience. 'sara' is probably going throughbsome hard times right now for reasons you may or may not know. She is taking her aggression out on others and don't be fooled when she takes being called evil and mean as a compliment because deep down inside that hurts. Try to be nice to her, give her some space and don't talk to her as often just so she can cool down from whatever predicament she's in. Good luck!