https://ew.com/tv/2018/10/12/crazy-ex-girlfriend-season-4-preview/

Co-creator and showrunner Aline Brosh McKenna says of Season 4: "Last season we dealt with the diagnosis and the mental illness, and then in the second part of the season, she finally defeated the dragon, which was her id embodied by Trent. Now we’re writing a more enlightened, present, grounded person who’s in less pain. In a funny way, this is the (enlightened) person she was pretending to be (in season 1) — now she knows what her tendencies are.”

ALSO:

Crazy Ex-Girlfriend has already beaten the odds by making it to Season 4 (http://www.vulture.com/2018/10/crazy-ex-girlfriend-season-4-review.html)
It’s the beginning of the end for Crazy Ex-Girlfriend, but they haven’t begun to slow down (https://tv.avclub.com/crazy-ex-girlfriend-is-ending-but-don-t-worry-it-will-1829708315)
Aline Brosh McKenna explains Rachel's imprisonment (https://variety.com/2018/tv/features/crazy-ex-girlfriend-season-4-premiere-interview-1202955421/)
Rachel Bloom looks back at her long Crazy Ex-Girlfriend journey (https://www.thedailybeast.com/crazy-ex-girlfriend-star-rachel-bloom-is-the-hardest-working-woman-in-tv)