Dave Bonta's "Junkie" is a very short poem about the cycle of craving, relief, and emptiness. It starts with a "usual urge for some glory," a wish to feel important or alive, and then the needle "hitting the vein." The poem sets the two side by side, so the hunger for glory and the hunger for the drug seem like the same thing.
The high arrives as a kind of collapse. The speaker falls asleep "a dog put down," a stark image that suggests passivity, loss of control, and perhaps a sad sort of mercy. There's nothing heroic here, which is the quiet irony after the opening wish for glory.
The last stanza brings the comedown. "The melancholy bruise / of having nobody" turns loneliness into a physical mark, as tender and lasting as the one on the arm. The mood is bleak and resigned. The speaker doesn't plead for sympathy; he simply states the loneliness that remains once the drug wears off.