Just want to point the difference between declining medical treatment and active euthanasia. In the US, a competent adult can refuse any medical treatment, as the lady in England did. The problems typically come when the patient is not mentally competent (unconscious, for example) and someone else tires to make that decision. As Rip pointed out, having a living will is a big help here.
The issue in Oregon is allowing doctors to actively end a patient’s life at the patient’s request, by prescribing an overdose of depressant medication.
Might seem like splitting hairs, but there is a difference.