Notice these are body and interior symptoms both — “crushes me to the ground,” “dwell in darkness like those long dead,” and then “my spirit grows faint,” “my heart within me is dismayed.” The psalmist doesn't separate his circumstances from his interior collapse. The oppression isn't just external pressure he's managing while staying composed inside; it has actually gotten in and hollowed him out. That's a more total description of distress than we usually allow ourselves to admit to — most of us try to keep managing appearances even while we're being crushed. And “like those long dead” is a striking phrase — not near death, but already positioned there, as if hope has already been buried before the actual outcome is decided.