Sure they can, because it is their choice regarding medical treatment. It's a choice just the same as any decision made regarding other goods and services offered in the marketplace. It involves Free will and is a gift from God, just as life is. There is no one that has the right to interfere with those decisions.
"For Christians, even supposed wishes, written or otherwise, might be considered a form of suicide. Playing with our own fate seems to me to be possilbly taking things from God's hands."
It is not suicide, it is the refusal to partake of the goods and services someone else is pushing. It's an exercise in Free will. Free will is a gift from God, just as life is. He does not interfere with it either before , or after death in these matters. Just as God honors a persons decisions, based on the reasons given, so should everyone else.
Suicide is killing yourself on purpose, when you would not otherwise die, or have to rely on the constant care of technologically competent others and their machines to live.
No, it is contrary to American justice to kill the disabled, even with their consent prior to becoming disabled. Otherwise, we would have to concede one of the following two things:
or
Regarding point number two, if all persons hold equal rights, and we grant the disabled the right to be terminated at their wish, all persons must be allowed that right. Society would have to accept a universal right to suicide.
The point I made earlier was that such a right to suicide cannot exist so long as the right to life is considered unalienable. Unalienable rights cannot be surrendered or transferred. This means, paradoxically, that unalienable rights restrain our freedom, in that they prohibit the surrender of our rights. Following this logic, there can be no right to suicide under the American creed.
So yes, you could go out in the marketplace and hire somebody to kill you, Dr. Kevorkian-style, but realize that such a choice cannot be accepted in American society for everyone else's protection.