There are multiple artists with this name:
1) Sadness is a depressive black metal/ blackgaze / post-rock band, primarily created by Damián Ojeda, from Oak Park, IL, United States, formed in 2014.
Bandcamp: sadnessmusic.bandcamp.com
2) Sadness was a death doom / gothic metalband from Sion, Switzerland, active between 1990-1998. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.