RANT ABOUT MY BEST FRIEND AND HER BF

His grandma found out they were dating and she wanted them to break up. He said yes but told emily it was a break. Well turns out he said they needed a break because he can't handle her and her depression. He said he somewhat hated her because shes got depression. She broke up with him and had told me shes been hurting herself again because of the stress. I saw him in the halls at school and slapped him. He questioned it and was like "wtf" and i said "yeah. What the fuck." He said "what?" And i came back and said "you're ridiculous." No wonder he wouldn't listen to me and my boyfriend, who we are his best friends, about him and emily dating only on school like most teen relationships. He doesn't want to be with her anymore. He can't handle her depression but thats when she needs him at the most. She stopped hurting herself when they were dating(over a year). His last true relationship ended with his girl committing suicide, but emily doesn't want to do that. She loves him with her heart and this is hurting her, my 'sister'.... i wanna beat him up so bad.