Although the onset of Nora's breakdown will be caused by a hormonal imbalance, something will need to be the spark that sets her suicidal thoughts in motion.  

She could discover that she has a Mexican mother.  Or something could suddenly bring back the memory of child that she lost at birth?

Keep in mind that it must parallel the life-cycle of cotton from seed to shirt. 

Additionally, what if James were not a cotton gin manager, but a professor of agriculture?