Falling4You2's "Only Star" is about the aftermath of a relationship that meant everything and then didn't last. The speaker begins by remembering the other person as a sun and a moon, the source of all light in their world. Now that person is only a shadow, a memory that taunts and haunts. The words "drown" and "haunt" suggest the speaker can't easily shake it off.
Then the poem turns. Two questions, "What were we? What have we become?", show the speaker trying to make sense of the loss. After that, the speaker claims a new identity: "I, my own star." There's some strength in that, a sense of carrying on and shining alone. But the setting is "the cold, dark vacuum of space," which makes that independence feel lonely.
The poem ends with more questions, this time aimed at the former partner: do you have light, do you have warmth? The mood is wistful and bittersweet, with hurt, lingering curiosity, and maybe a little hope that the other person is also not okay.