Mellow/Somber Ambient Albums

eluvium!

no one can resist the beautiful sadness of this
https://www.youtube.com/watch?v=8rluU6BGpKw

A Winged Victory for the Sullen (adam wiltzie from Stars of the Lid plus piano composer dude Dustin O'Halloran) has a really emo name but the S/T from last year will make you stare out the window and agonize about your past in a good way

second bvdub, in particular seek 'the art of dying alone' every song title reads like a depressed madlib

Why didn't anyone tell me that A Winged Victory for the Sullen was Adam Wiltzie?? That sounds liek my kind of afternoon.

I was gonna say, the correct answer here is Eluvium, but you figured it out on your own. Well done.

If I were you, I'd get everything he has ever done. One of the finest, most beautiful catalogs of music ever.

have you ever heard "return to innocence" by Enigma

Most classic ambient (pre-Aphex, and non-New Age) can qualify. Since you like Hammock (who I think are sublime), can I suggest you look into the back catalogue of Jeff Pearce:

https://www.youtube.com/watch?v=TGTC_LbsqiM

jasper, tx - a darkness
steve roach & vidna obmana - cavern of sirens
coil - love's secret domain

Celer qualifies here as well, especially the albums with just one or two pieces

https://www.youtube.com/watch?v=nPGSEJEYoGQ

haha, I love Sasha's Airdrawndagger but I don't think any song from it fits as a soundtrack to my breakup.

My recommendations for bummed-out ambience:

Blithe Sons - We Walk The Young Earth
Rameses III - I Could Not Love You More
Richard Skelton - Landings
Grouper - Dragging A Dead Deer Up A Hill
Richard Youngs - Sapphie
Loscil - Endless Falls
Scott Tuma - Not For Nobody
Mountains - Sewn
Nils Frahm - Felt

Bummed out-ness guaranteed on almost all those (at least one of them is dedicated to a dead wife and another is about a dead dog). The last two are somewhat less down in the dumps, but they are both v v pretty.