Of course society has to accommodate the exception and if a living will or personal directive is required there can be no abuse.  Neither is there any problem dealing with abortion if the mother so wishes.  It is not the business of society to decide the rights of individuals providing that those rights do not harm others.

Compassionate physicians often prescribe massive doses of pain killers to terminal patients knowing that they will likely cause death.  Others, particularly when prompted by family, will use every futile intervention that may prolong life by days, weeks, months or hours without consideration of the patient's suffering.