I'd advise her to log off. She's 17 years old? There's no logic to this behaviour, these negative emotions, and how she handles social media. Although she probably doesn't understand that posts like these garner more attention, and they're posted on forums like this for people to make fun of her like a clown at a circus. I don't blame her.. she just needs guidance.
She should delete social media. Social media is ruining celebrities and the like. I know she may want to be just a normal 17 years old, but she's not. If it is causing her this much stress/trouble then it's time for her to step away and find another way to communicate to her followers and supporters bye