Jeez I don’t say this lightly but this is a massive parenting fail on your behalf.
Why has this poor child had access to the internet since the age of 9 to make up fake personas.
You are her parent not her friend. Do NOT be afraid to be seen as the bad guy by putting rules in place if they are to ultimately protect her.
No wonder she doesn’t have many real life friends if she’s been given unprotected access to all of this.
She should know that a smartphone is a privilege not a necessity and that you are the one paying the bill.
You are allowed to have access to her devices whenever you see fit.
She should not be able to take her phone/tablet etc into her bedroom or keep it at night.
The highest parental controls should be in place on all tech.
She shouldn’t be on any form of social media like Twitter for god sakes. My heart breaks thinking about the absolutely vile things that are on there that she’s most likely come across.
Get this poor child out into the real world. Join clubs, go to the park, let her have the childhood she deserves and needs.
The fact you don’t see how terrible this whole situation has been from a very young age is worrying.