cruelty

my best friend for 7 years last Wednesday singled me out of our group of friends and posted a bunch of hateful things about me and so did my so called friends she did it 2 years ago as well then exact same thing I don't know if I should forgive her or just drop her I only have 2 friends left from that group and then rest have all said they don't want to be my friend anymore I have tried talking to me and they flip me off??? I have had really bad anxiety since then and can't sleep anymore I have been harming myself and not eating much anymore I don't know what to do plz somebody help...