Deerskin

Tokens worth the finest treasure in this world or any other, tokens no living man should be able to bear; and he threw them into the fire for the love of your mother, and felt no regret. For, he said, all the joy he needed was in your mother's eyes; and he could withstand any sorrow so long as he had once known that joy.

...a dog's love, once given, is not reconsidered; it just is, like sunlight or mountains. It is for human beings to see the shadows behind the light, and the light behind the shadows. It is, perhaps, why dogs have people, and people have dogs.