Nice contest! Loved this idea of participating in the comment section! :)

The saddest song I know I believe it's Lazarus by David Bowie.

Since the very first moment, you get to hear notes that simply get you down, just like that. I've been a fan of Bowie for my entire life and it's simply heartbreaking to hear the pain and sorrow in his voice, specially when he's always been so sparkly.

Aside from the music itself that knows how to make you feel his sadness, lyrics are just devastating and show an incredible amount of vulnerability, Bowie's almost saying goodbye and his voice is so down if you compare it to his regular recordings. I get goosebumps at the moment of writing this, this just breaks my heart.

At the time of that recording, Bowie was fighting against cancer for quite some time and just a couple of days after releasing that last album, he passed away. I believe this was his perfect way of saying goodbye.