If I had to guess, with all the interactions I've had with this shitwit and everything else I've seen:
Traumatic child experience, unresolved - likely by a trusted family member. Leading into an attention issue, desperate for some kind of purpose or validity - always trying to fill that empty void, while using escapism as a coping mechanism for avoiding her own deep-rooted personal psychosis.
Got into the cosplay/anime community, found an unconditional support mechanism. Is now latching on and creating a feed-back loop of self-gratification. (For anyone who's played Portal 2, much like how Wheatley reacted to the elation of creating a "test", and then getting frustrated when he didn't get the same dopamine rush when he made the same "tests")
The walls are literally falling in, and we're witnessing (in real-time) the mental degredation of a human being playing out on social media. Honestly wouldn't be surprised to find her floating in a river in the next 5 years.