For my sister!!

Ok, so my sister's boyfriend broke up with her. He said some very hurtful things to her, and she is sad all the time. He dissed on the way she looked, who does that to an insuccure girl! He was a totall jackass! He keeps going to her to talk cuz he wants to be friends and that makes her cry (in privat). What can I do to make her get over him or at least chear her up.