Did you find the ending happy or sad?
Rico is dead which is sad of course, but at least he taught Joe some of the most important lessons in life so despite his sense of failure when he visits his father's grave, it's apparent that his short life was not a complete waste.
Although it is unclear what is exactly in store for Joe, if his goal is to live a happy, normal life, then the future seems promising for him as he has his whole life ahead of him.