I don’t think this issue is on par with “women’s rights” over their bodies issues. She was likely misinformed/misdirected by her crazy mother. This will give her the opportunity to become an adult and then make her own informed decisions. As she goes thru treatment, she will likely meet others who are fighting for their lives and she will become grateful that she has a good chance. She will also learn a lot more about her disease and realize why she needed this treatment.
Her mom sounds nuts…a total loon.