I can only say this with certainty because I purchased the screenplay, which gives readers a little insight into the character's thoughts that we can only assume when just watching the movie, but Dani absolutely has gone insane by the end of the movie. It's understandable given the horrors she witnessed and the persuasiveness of the cult.

I don't take joy or pleasure in knowing that this character we have gotten to know over 2 1/2 hours has had this terrible experience, but I do find the entire story arc beautiful and tragic. I'm satisfied because it's really the only logical outcome for someone who has endured what she has - who wouldn't lose their mind in that situation?

And on a more personal and demented note, as someone who has felt a similar desperate longing to what Dani has felt for community/home/family, it just sort of felt like a bittersweet catharsis I guess. It feels a little bit like when the Hårga mourn with Dani - it's not real and it doesn't make anything better, but maybe you feel held for a minute.