The speaker describes a numbness that has turned them into something less than a person. They feel like "a body of vessels, of breathing oxygen, and blinking lights", a collection of working parts rather than someone with a inner life. The title word "nomad" and the line about being "on the road" suggest constant movement, and the speaker seems to drift from person to person, "through the hearts of many", without finding a place to settle.
There's a tired detachment here. Whatever people say or do, the speaker "wouldn't care," and even the effort of trying "to see what you can, and be what you aren't" feels exhausting. That last phrase hints at pretending or shapeshifting just to get by.
The ending is the most striking part. The heart isn't dying; it "just can't be felt anymore." So the problem isn't a lack of love or life, but a loss of connection to it. The mood is quiet, weary, and lonely, more like emptiness than loud sadness.