Images of death remind us of how fragile and tenuous life is. These moments we experience are fleeting. We could be dead tomorrow. Better to reach out for something today, even if we regret it later, rather than never to experience it at all.
Although many dismiss it as "a mexican version of American Pie", they fail to see the complex message behind this movie. These are not grotesquely horny teenage boys. These ARE teenage boys. This is not a woman who decides to placate fantasies and such, but someone looking for something. Someone who would, if asked in a questionaire in a magazine, "make decisions without regret based on today, rather than worry about tomorrow."
The sadness of two friends who drift apart. But things fall apart and nothing in life lasts forever and ya it's sad. But it is enevitable that nothing lasts forever and so you have to savor everything, even the pain.