The speaker describes feeling like a ghost: people walk straight through them because they cannot see what is really there. The speaker even calls themselves "the monster in front of them," which suggests they feel either feared or deliberately overlooked. That loneliness is the heart of the first half, and the short, plain lines make it feel quiet and heavy.
Then something changes. A girl approaches and asks why the speaker is so sad, calling them "young lady." That small act of noticing, and the simple kindness of the question, is enough to make the speaker realize they are "back." The final lines, "No longer ghost, / No longer dead," repeat the same pattern, like a relief being said out loud.
The mood moves from isolation to warmth. The poem seems to say that being unseen can feel like not existing at all, and that one person paying attention can bring you back to life. The ending is hopeful without being loud.