Demi Lovato has always been outspoken when it comes to being a bullying victim, and the singer took to Twitter Sunday to blast those harassing her and others on the social networking site.

demetria lovato
It really surprises me the hateful things people say on the internet.. After all the awareness of cyber-bullying... I mean wow. So sad.

demetria lovato
Praying for all the people in the world who feel it's okay to bully people over the internet because if you are one of those people, then..

demetria lovato
You must have had something really terrible happen to your childhood or you're really sick in the head. Must suck to be born without a heart

Lovato, whose eating disorder documentary, "Demi Lovato: Stay Strong," debuted on MTV in March, has admitted that online bullies eventually led her to hurt herself. In the film, she refers to "comments from strangers online, saying 'This girl looks horrible, she looks fat.'" Those hurtful comments contributed to Lovato's struggles with eating disorders and cutting.

Today, Lovato is on the mend and hopes to help other teens who are going through tough times. She's currently fighting, along with other celebrities, to repeal the "R" rating on "Bully," a new documentary centering on the intense bullying many children and teens face today.

Lovato isn't the only young singer to take a stand against anonymous Internet haters, either. Miley Cyrus recently called on Twitter to take action against online bullying after she received threatening messages via the site.

Miley Ray Cyrus
I wont tolerate someone telling me 2 die. I think Twitter needs to take some responsibility and make it a safe environment!

Check out photos of Demi Lovato below:

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