Nightingale is a tough nut to crack. Lytton-Strachey brought this out pretty well a century ago in his mini-biography of her in Eminent Victorians. She was a single person set up against an entire system of studied neglect who managed through pure will to make permanent changes in that system, and in the entire country attached thereto, and a character that large and impressive is bound to have some pretty big foibles.
Namely, she was ruthless with any signs of weakness in the people who worked with her. They could be at her side for ten years, giving every second of their lives for her cause, but as soon as they got tired and wanted to slow down, they were dead to her. She gave increasing blocks of time to religious speculation and the development of programs to indoctrinate the working classes for their own moral good. As she grew older, she grew into a spidery reclusive issuing dicta from her room, insisting increasingly on her particular version of the ideal hospital even as the potentially deadly flaws in it became apparent. But then she became a bit senile, and was by all accounts quite pleasant thereafter.
– Count Dolby von Luckner