To realize our 'human body' is not really us and only similar to a suit of clothes to be eventually discarded is real progress! Whether she gets 'cremated' or not is up to her.
It is interesting how enlightenment happens ----- one area at a time when it is needed.
This is a good sign. Give her some positive feedback about her decision such as talking about embalming fluid leaching into ground water, and resources spent (wood, metal, etc.) spend on our culture's death rituals.