I haven't seen the movie yet, but some people speculate that Jennifer Lawrence's character -- Rosalyn Rosenfeld -- has a mental illness, possibly bipolar disorder. Lawrence said of her role, “She’s a manic-depressive alcoholic, and I couldn’t wait. Plus, I got to make out with Christian Bale.”

The director, David O. Russell, has a son with bipolar disorder. I read an article awhile ago which mentioned that this influenced his work.