DSX very good of you to post this at a difficult time for your family. Your SIL had a very difficult time overall. Do you know what her treatment consisted of?
You do not mention what her stage of disease was or her age. Sometimes these things also can play a part in how the body copes with what is an effectively aggressive treatment regime. Sometimes we need all to recognise that not everyone has an easy ride with this disease, I also fall into this category. Your point about being vigilant about your blood results and persisting with the doctors for supportive treatment is important.
Dusk