It's just the most amazing thing to love a dog, isn't it? It makes our relationships with people seem as boring as a bowl of oatmeal.

Dogs are a really amazing eye opener for us humans because their lives are compressed into such a short period, so we can see them go from puppyhood to adolescence to strong adulthood and then into their sunset years in 10 to 12 years. It really drives home the point of how finite all our lives are.

A person can learn a lot from a dog, even a loopy one like ours. Marley taught me about living each day with unbridled exuberance and joy, about seizing the moment and following your heart. He taught me to appreciate the simple things-a walk in the woods, a fresh snowfall, a nap in a shaft of winter sunlight. And as he grew old and achy, he taught me about optimism in the face of adversity. Mostly, he taught me about friendship and selflessness and, above all else, unwavering loyalty.

Such short little lives our pets have to spend with us, and they spend most of it waiting for us to come home each day. It is amazing how much love and laughter they bring into our lives and even how much closer we become with each other because of them.

. . . owning a dog always ended with this sadness because dogs just don't live as long as people do.

In a dog's life, some plaster would fall, some cushions would open, some rugs would shred. Like any relationship, this one had its costs. They were costs we came to accept and balance against the joy and amusement and protection and companionship he gave us.