natalie in the original series vs now

i'm rewatching her first seasons on the original 90 day in tandem with resort and i cannot believe how much she's changed. in the original series she's a little silly and whimsical but ultimately sane, kind, and just all the way there mentally.. how did she get to the state she's in currently? moving to LA? being led on by josh? actual mental damage? or is it just an act she's putting on to stay on the show?