As I said, we are lacking the information about the most likely long term effects of the treatment. I do care about that, and it might change my mind.
If this girl was 9 years old no one would blink that the parents were going to do treatment assuming the treatment is not terribly abusive and the long term prognosis is very good. The 9 year kid wouldn’t want to do it either most likely. They don’t want to get a needle or be sick.
I know plenty of people who have been through chemotherapy, one of them in particular I didn’t think she should do it and I still think she shouldn’t have, but she doesn’t regret it. Another, I think I described him above, I think they should have let him die after the first set if treatment, which was a bone marrow transplant, didn’t work, but they tried again. He didn’t want to do it, but he did. He was in his early 20’s. He didn’t want to die, but he didn’t want to go through the process for such low odds of success.
The girl certainly can hang herself tomorrow if she wants to die.
All of you saying she should be able to choose to refuse the meds, what if you came home and found your teenager or sibling dying (God forbid) from an overdose with the suicide note next to them? Would you watch them die? Or, would you call the ambulance, have them stuck with IV’s, stomach pumped, shocked if their heart went haywire, and drugs pushed into them to keep their blood pressure up and whatever else needed to be done?
17 year olds are notoriously depressed and borderline suicidal even when they are perfectly physically healthy. They aren’t trustworthy to judge life.