Also, I don't know who Marsha and Jan are, apologies, so that part of your comment is lost on me.

Brady Bunch. I'm way older than you.

I missed the psychologist part in your original edit. That is a major detail point. My fault for glancing over the edit.

So there seems to be very deep seeded issues for a 15 year old that sounds like a 21 year old is doing the best she can do despite parents who think it's just a phase. (Which is a very Hope and Pray way of dealing with this situation)

She's stuck in an addiction/pattern of behaviour. She needs to drop this addiction, but in order for it to be successful, something else needs to come in to replace that addiction, or she'll revert to said behaviours.

There's a Ted talk that talks about the core of addictions all being about lonliness.

She needs to be pushed out into the world and encouraged to engage with everything and anything to see if there's something that she's passionate about.

And as a base rule. Since you can't controll it for anywhere else, a new rule that she cannot facebook in the house anymore or any other social media which she uses to catfish people. That's a privilege that she has lost.

This is a simple keyword block for her computer or any other device she owns via router admin.

Sorry. Don't mean to make you feel like you're being jumped on.

Text on screen seems to do that.

I'm not accusing you of ignoring or abandoning her. I'm just pointing out the fact that what she really needs at the moment, you're unable to provide.

But yes, she wants attention, and the type of attention she wants she's clearly is stating that she's not getting from you or anyone in your family.

Now it's time to find out what that attention is, and how it can be replaced with something more constructive.