Why do people have the nerve to talk bad about you , and wont even say it to your face?

okay , this girl in my school named ciara deshotel talks about me and my friends and she wont say it to my face or my friends. i have very nicely asked her many times to stop and she denies that she does it , so i decided i woudnt talk to her again , and or warn her friends that she talks about us . it really hurts my feeling and im really tired of it . she is frightend that she is going to get in a fight next year at school so she is deciding on doing homeschooling instead of public schooling . her mom messaged me on facebook saying that i am a bad person which she dont know me so i dont care what she has to say . she also has no friends at all her mother contacted me recently and said to leave her alone and i said i wasnt bothering her and she also said to leave her friends alone .. so im deciding on who to leave alone because she doesnt have any friends. nobody likes her , she is childish , to faced and fake . now i want her to read this to explain my feelings towards her and to let her no im not dealing with herr shh!!!!!t anymore and by the way lmao she dont hurt my feelings she makes me laff how she just has no life and decides to talk about me , shes broken . she is falling apart , you also may look to add her on facebook and get to know her and see what i am meeaning about how stuck up and dirty she is ..... AND she knows that i said all this because i send it n a message showing it to her so apparently im not the one who is scared , why coudnt u jus tell the truth honestly maybe none of this woud have happend ...