You seem to be ignoring all the larger concepts of human dignity and focusing it on one final choice at the end of life.
"Do we possess dignity and a right to life by virtue of the kind of entity we are, namely, a human being—the one type of bodily creature known to us who has a rational nature? Or is dignity something we possess only by virtue of our acquisition or realization of certain qualities (immediately exercisable capacities) that human beings in certain stages and conditions possess (or exhibit) and others do not, and that some possess in greater measure than others, e.g., self-awareness, consciousness, rationality?"
Read more:
http://www.touchstonemag.com/archives/article.php?id=20-01-004-e#ixzz3o0uBhEN5
“Death with dignity” offers not only an escape from pain and humiliation, but a rational and apparently noble way to leave this life. All it requires is that you declare yourself God. Make yourself the lord of life and death, and you can do what you want. All you have to do, as a last, definitive act, is to do what you’ve been doing all your life, every time you sin: declare yourself, on the matter at hand, the final authority, the last judge, the one vote that counts."
http://www.firstthings.com/web-exclusives/2010/11/death-dignified-by-christ
Hence, in my view, the concept of human dignity is really only safe in a society with a firm belief in the equal dignity of human persons. Concerns have been expressed about rationing care, depriving people (especially those with diminished capacities) of needed care, and even of encouraging people to die. These are all serious and legitimate concerns, and their presence suggests an uncertainty about our continued commitment to equal personal dignity. (Gilbert Meilaender)
Read more:
http://www.touchstonemag.com/archives/article.php?id=23-02-036-i#ixzz3o0wyp6RG
People are losing the real definition of dignity.