Franny's crisis and resolution is the heart of Franny and Zooey. To understand her character, we have to think about what makes her so upset, why she is upset, and how she manages to pull herself together at the end of the novel.
Because Franny doesn't hold back when it comes to her problems, we can take pretty good stock of what ails her by looking at her list of complaints both in "Franny" (as outlined for Lane) and in "Zooey" (as detailed to her brother).
There are two sides to Franny's crisis. The first is that she dislikes much of the world around her. She thinks college is an ego-fest that's more about showing off than anything else. She feels that she's missing important things like wisdom and spiritual advancement, while wasting her time accumulating knowledge as though it were treasure. She's afraid to act because she doesn't want to become egotistical like everyone else.
The second side to Franny's crisis has to do with herself – she resents that she's so judgmental about college, the people around her, and the acting world. She might have issues with them all, but she blames herself for judging them. That's why she feels so guilty for picking at Lane during lunch, and seems to go back and forth between despising him and trying to play the part of the doting girlfriend. At home on the couch, she seems to be as angry with herself for having a crisis as she is frustrated with the causes of her crisis in the first place.
We don't get much from Franny in the way of an explanation – why is a seemingly ordinary college girl freaking out like this? Elements of Franny's crisis are actually fairly normal. Many students do have some kind of identity crisis during college years. But there are also elements that are definitely out of the ordinary.
The Glass family is a peculiar bunch: kid geniuses, two deaths in the family, ex-vaudevillian parents, child celebrities, and a distinct spiritual bent to a somewhat premature education. Zooey seems to blame most of the problems on these last two: "Those two bastards got us nice and early" he says of his older brothers, adding that he and his siblings have "'Wise Child' complexes" and "never really got off the goddam air" (Zooey.6.63).
Indeed, Franny's crisis does have its roots in the religious books she carries around with her, and those books, rather symbolically, came from Seymour and Buddy's room. Her interest in religious philosophy comes from the education her older brothers gave her at a young, impressionable age. Just as Zooey can't sit down to dinner without saying the Four Great Vows, Franny can't sit through a college class without wondering if her soul is getting as much attention as her brain.
But if Franny's family is the cause of her crisis, it is also the source of its resolution. Zooey's arguments – which we discuss in Zooey's "Character Analysis" and in "Symbols, Imagery, Allegory" – teach Franny new, important spiritual lessons. In a nutshell, Zooey points out the hypocrisy of her point of view, teaches her to appreciate beauty in the world, and reminds her that everyone – including that professor who bothers her – is a part of Christ.
Additionally, Franny's oldest brothers seem to play a part as well. The idea of the "Fat Lady" came from Seymour, after all, and Franny only opened up to Zooey on the phone when she thought she was speaking to Buddy. Franny's crisis is a family issue, and so is Franny's epiphany at the end of the text. Check out "What's Up With the Ending?" for more on Franny's resolution and the novel's conclusion.