Are we going to blame the barista who got her order wrong, the thief who stole $20 dollars out of her purse, the washer-machine that ruined her favourite dress, or the boy who broke up with her (theoretical occurrences).
No, no, no, and no. I'll refute point by point:
The barista - without further information it is most reasonable to conclude that the barista did not have malicious intent, mistakes happen
The thief - obviously the thief has malicious intent in that they stole money but not intent to kill her as you made no mention of attempted homicide, they were after the money, not the girl
the washing machine - non-sentient appliances cannot be blamed for anything as they lack intent
the ex-boyfriend - unless he also joined in harassing her then no, again, lack of malicious intent
Now compare that to two girls repeatedly harassing, intimidating, and generally being little shits over an extended period of time with clearly demonstrated malicious intent ("Go drink bleach and die")
One of these things is not like the others...