Admittedly, Mr. Huckabees communication abilities were compromised by the stroke, but considering how intensely he stressed his decision not to die like his mother before the stroke took place should be more then enough to satisfy Gloria when shes deciding whether to use her own judgment, or to go with his expressed wishes. Will clearly felt, when he was of sound mind, that Gloria would respect his wishes, which is why he made her responsible for such a decision in the first place.
The main ethical issue regarding this type of decision is the question itself, does a person have the right to end his or her own life? Truly, when looking at a terminal illness situation such as Will Huckabees, the only humane thing to do is to provide the palliative care, even if it does result in this death.
The conditions under which it is appropriate for denial of palliative care would really depend on the individual situation, and whether or not it is a terminal case. But if the patient is truly in excruciating pain, and there is nothing else that can be done to improve their situation, how could it not be acceptable to grant that patient palliative care? Addiction to painkilling medication is irrelevant in this type of case.
Hospice is a last step which tries to make the patient as comfortable as possible during their last time alive. Considering that it is stated in the case study that Mr. Huckabee was crying out in anguish from the pain he was enduring, a move to a hospice situation from where he is at the point of the story may be too much for him to handle.
In conclusion, Mr. Huckabees wife Gloria needs to consider her husbands clear wishes about what he wanted to happen to him regarding his life at this critical point, and to let him receive palliative care, even if it is likely to cause his death.