To me taking the responsibility of "guiding" someone through their life is a bad idea everyone has to find their own way. I feel that I got enough problems in my own life without trying to go through and fix everybody else's

Ignoring sam harris for example.

Some people in this world have a need to follow something or someone. I am not sure that one can in any way brake that pattern, only put them on a pattern that is not dangerous or destructive.

If you go straight on all you will get is resistance. May I suggest you talk about sales as a career. Then give a book or show her videos on sales techniques. If she does not want to listen? Say your thinking of sales and what she thinks about the techniques? When she sees the way simple physiological tricks can alter someones thinking. She may put things together and sort her self out.

What's the name of the woman?

Read some psychology textbook chapters on cults. Fascinating stuff. You will gain lots of insights as to what's going on inside your friend's mind.
Then you could (very slowly & gently) try Daniel Dennett's 4 rules for arguing:

1. You should attempt to re-express your target’s position so clearly, vividly, and fairly that your target says, “Thanks, I wish I’d thought of putting it that way."
2. You should list any points of agreement (especially if they are not matters of general or widespread agreement).
3. You should mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.

That should hopefully defuse the Backfire Effect.

Keep asking questions and be aware if you sense any distress from her. And be a trusted friend. That's all you can do.

You can try street epistemology on Facebook. There ARE some very experienced people on the site. But if you have regular contact and communicate with this person, you may start by getting them away from the surrounding influence and ask questions. A LOT of questions.

You can do what you can, but I think it might end in failure. The brains of cult followers just do not perform normally. Just my opinion.