To the surprise of no one, high school girls and boys want to appeal to each other, and the latest zoomy trends are post-ironic 1488 HH chudcore. But this girl's problems seem to stem less from the specific memes (I think anything could have radicalized her) and more her upbringing, since if you dig into her home life she's been separated and reunited with her parents several times, both of whom were huge drug addicts. The father has been trying to clean up his act according to his Facebook, but it might have been too little too late.
We don't have a choice. Her upbringing is only going to get more common; the flow of stuff like fentanyl isn't slowing down and realistically never will. She wouldn't have been groomed if there weren't drugs for her parents to get themselves addicted to and they subsequently raised her properly.
The reality is her life is tragic, it's okay to accept that and still condemn her obviously horrific actions. Certainly her life was more tragic than most shooters who were mainly from upper middle class/stable families and generally acted out of nihilism/boredom (Dylan and Eric at the least probably got fucked up by psy-ops and anti-depressants).
But the thing is, people can pull themselves out of these mires if the influences around them when vulnerable do not encourage their worst behaviors. Someone her age with her experiences on the modern internet? Whilst being female? This was always going to happen with the current net.
Since someone is inevitably going to use the "THEY WEREN'T GROOOOOMED" line again based off some random definition, or call this all a conspiracy:
It is grooming when a group, even if not separated that much by age, use a young girl as an outlet for degradation and degeneracy. It is grooming when they clearly knew what they were doing. It is grooming when you intentionally fill someone with ideas of killing themselves/others "as a joke" or as part of a group humiliation ritual.
Have no doubt, they got off to humiliating this girl, they wanted to mindbreak her, then they panicked when she truly broke and did what they had been telling her to.
It is imperative we continue to dig, expose, archive, and do not lose focus. If her groomers get away with this now, they will do it again.