I have a cat, now 18 years old. Several months ago, he seemed to have given up on life. I considered putting him down, he was that "bad off". Then, I thought, just make him comfortable. Ease his way. So I cleaned his head twice a day, combed him out ... and then I realized he was "down" because he could not do this for himself. It did not matter if I did it for him, he just needed to be clean.
Well, he is still here. Cranky, as always. As healthy as an 18 year old cat could be.