If she hasn't done anything yet, and hates what her life has turned into, why doesn't she just stop?
That's a huge problem, especially for pooners. Imagine you're a girl in her impressionable adolescent years as a plain, ordinary, certainly awkward teen. Maybe you're a bit on the spectrum, but otherwise just run of the mill. Then you decide you're an enbie with a new name and different pronouns. Suddenly you start getting praised and lauded for your stunning bravery. If you've got stupidly permissive parents, they're affirming every thing you do. Even non-family authority figures are bowing to your will by addressing you by your new name, etc. And if you're terminally online, you've got a whole new herd of "friends" applauding and encouraging you.
Then maybe you decide you're really a boy. And now you're really special. More accolades, more applause. And all of your new friends keep on encouraging you.
And no one in your life really gave much push-back.
Now imagine the fog of retardation that are the teen years lifts. In your soul, you know you're really a woman. But as such, you're also more likely to be a people-pleaser. Do you want to go through the embarrassment (self-imposed) of telling the people in your life that the past six, seven, eight years were all a mistake? Are you going to have the self-confidence now, that you lacked when you were a teenager, to face the intense scorn and abuse from your online "friends" for desisting and "betraying" them (the cause, the movement, whatever)?
And since no one in your life was ever strong enough to say "no" to your pretenses, you now have no one to confide in honestly about your mistakes free from the scorn or embarrassment.
Maybe now
you see how "just stop if you hate it" isn't as easy as all that.
It's my most sincerest wish for anyone who reads this and who has a pooner in his life to be that person who refuses to go along. And to let your Li'l Pooner know, unmistakably, that you love her, and that she will always have at least one person she can come to later without embarrassment, and who won't judge her for stupid shit done when an adolescent.
(Faggot dadism over)