I didn't read this book for years, because I didn't think a story about a guy and his crazy dog would be very entertaining. Plus everyone said it was sad. I heard the same about the movie, so that's why I never watched that. Then a few weeks ago I was at my parents house and the movie was on so I thought, why not, I'll watch it. And I liked it. Yes, the ending was sad. It usually is when a pet dies. So I figured that I would read the book. And I liked the book too. After I got done reading it I was trying to figure out why I liked it. And I think the reason was was because after all the trouble and chaos that the dog causes, they still keep him. A lot of people would have gotten rid of a hyper active dog who eats everything and gets slobber all over everything. And that's sad. So I really respected the fact that they kept him and never gave up on him. Its like with my cats. I hate when they pee on the bed or scratch at the door, but they do prove entertainment and give me a reason to get up everyday (someone needs to feed them), so I would never give them to a shelter like some people would've. I think people need to remember that pets aren't perfect. Marley wasn't perfect, but they loved him anyway.
So, yes, you should read this book. Or if you don't have time, then watch the movie.