In the 19th century, how was women's mental illness viewed by society?

In the 19th century, women's mental illness was not considered a serious issue, as Charlotte Perkins Gilman's "The Yellow Wallpaper" demonstrates. Doctors, rather than analyzing female patients' mental symptoms, simply prescribed a "rest cure." Like the narrator in Gilman's story, women were expected to heal, simply by resting. As the story reveals, however, the cure could prove far more detrimental than beneficial, and it is no coincidence that Gilman's narrator goes mad.
Gilman explains her motivation for penning the short story in her expository text, "Why I Wrote the Yellow Wallpaper." In it, she explains that the account is based largely on personal experience. "I went home and obeyed [the rest cure] for three months," she writes, "and came so near the borderline of utter mental ruin that I could see over."
Hence, she wrote the story largely to spread awareness about the true results of the rest cure. Moreover, after reading "The Yellow Wallpaper," her physician ceased prescribing the treatment.