The poem is about a girl who feels too sensitive, too expressive, for the people around her. The subtitle sets up the clash directly: "poetry girl against deaf world." She isn't just someone who writes poetry. In the poem's words, she *is* poetry, as if it's her whole nature rather than a hobby.
The world, by contrast, is "still learning the / Alphabet." That's a sharp image. Poetry is built from letters, so a world that hasn't mastered them can't possibly read her. The word "deaf" in the subtitle adds to this: it isn't that people are cruel, exactly, but that they can't hear or understand her yet.
The title, "Broken Princess," suggests she is hurt by this gap, and the speaker seems to look at her with sympathy and a little admiration. The mood is quiet, wistful, and lonely. The short, stretched-out lines feel like a sigh, leaving her isolation hanging in the white space around the words.