Emma was not too smart

I am still reading the Kingdom of Nauvoo, where Emma Smith is trying to combat Polygamy. Something that nearly everyone else in Nauvoo, was in favor of. Eventually, Polygamy was forgotten, but this was after she was dead. 

She must have known of this situation, but persisted in her moral campaign, which got her nowhere. The main result of this, was the total ignorance of her sons who knew nothing of what was going on. 

She stayed behind, in Nauvoo, when nearly everyone else had left.