Um, this is a strange question, I'm REALLY concerned about someone.

I don't think that girl is crazy.
u do need to care for yourself as well and to be honest, I am also not a very helpfull person but that has other reasons.
And I certainly won't act nice to people who hate me.
I don't think anything is wrong with her.

Perhaps she was asking out of curiosity. Though, that was mean of her to say that no one cares about you. u should care about yourself. Like what the other person said, don't be nice to people who are mean, hateful, spiteful etc. They don't deserve it, the best thing u can do with those people is to ignore them. Don't be mean back, that will only make matters worse. I know it's easier zei than done but u should give it a try.

Again, I don't think she's crazy I just think she was curious to your behavior. She could have been a bit meer polite about it. Also, it's normal to care about what people think of you, it's part of being human (everyone has their insecurities). Nevertheless, that doesn't mean u should let what people think of tell u dictate who u are and what u do. Hope this helps