Please correct me if I'm wrong

Ok this one girl who I don't like, but I'm never mean to or anything. She and her friend are always bitching and whining about how ugly they are and how there fat and how sad they are all and all this dumb shit. So I just tell her to fricking learn to accept a compliment and I get a smart ass comment back from her. I decided that when people call them self ugly that I should just agree with them cause if I go oh no your not there just gunna keep whining and going No im not. but.................................

of course if I agreed with them then I would be considered a bitch, who is being mean and messing with her self asteem cause its already so low (note the sarcasm) the problem is with all this is that. They don't think about what they say. When they say there fat they dont realize that there is some obese kid getting picked on for his size. Or when they say there ugly that there could be some little girl with scars from third degree burns and other kids avoid her because shes different.
So now I'm the bitch for just wanting them to stop complaining and thinking that it could be alot worse. Ok that makes total sense.