Hawthrone's poem is a short list of three kinds of pain, each described through taste. Heartbreak tastes like soap, which is bitter and artificial, the sort of taste that makes you want to spit. Crying for other people tastes like the sea: salty, vast, and in a way natural, as if sympathy is something larger than you that you wade into. Losses you cause yourself taste like nosebleeds, metallic and a little shameful, because you know where the blood came from.
The title, "Rash decisions," hints that the last kind of pain is the one the speaker knows best. Nothing in the poem tells us what the decision was, and that gap is part of its power. The final two lines are blunt: when all three happen at once, "You're dead." That may be exaggeration, the way people say a bad day is killing them, or something heavier. The mood is dry, bruised, and darkly funny, with a flat tone that makes the ending land harder.