A gruesome question, I grant you, but this whole situation is gruesome.
In searching for anything good about this tragedy, I am thinking that Terri's life's "purpose" might be that we reexamine our laws, our hearts, and our own purpose in life itself, thus bringing about an awakening to our own relationship w/God.
The cremation and disposal of the ashes is why I became disgusted with Michael Schiavo. His decision is not motivated by anything but spite, IMHO.