I searched for it and it shows something like:
“Cafe Müller “(1985 Television Version)
Premiered: 20 May 1978, Opera House Wuppertal
Director & Choreography: Pina Bausch
Music: Henry Purcell /“The Fairy Queen” e”Dido and Aeneas”
Though I couldn't get the same piece of music. There seem to be too many songs.
You can check this link (http://www.pina-bausch.de/en/pieces/cafe_mueller.php)
After some more Googling I think this particular clip could be from the movie 'Pina'. Is there any chance you have seen the movie?
For 'Cafe Muller', it shows what I've already posted but listening to the music I've mentioned it actually is a 'Lament opera' not the 'instrumental' that is on this video. Maybe this clip is from the movie that used their own soundtrack instead of Purcell's opera. Alas! I can't find this exact instrumental piece from the music either, though I still haven't explored all their soundtracks.
This is my best guess, but I'll keep searching because I'm going crazy over it. If you've found something kindly update your post. Hope it will give you some idea.