"Roto" means broken, and Matisse spends the whole song blaming one thing for it: fate. It starts with a chance meeting, "Fue casualidad o buena suerte" (It was chance or good luck), finding her "entre tanta gente" (among so many people). They were drawn together "tan obvios como dos imanes" (as obvious as two magnets). Then something pulled them apart, and he honestly does not know what: "Fue la Luna o el Sol" (Was it the Moon or the Sun), or something bigger than the two of them.
The saddest part is how close it came. "Estuvimos a nada de que nos pasara" (We were this close to it happening to us) uses estar a nada de, a lovely everyday phrase for being a hair away from something. Now he is "clavado en el mismo lugar" (nailed to the same spot), and it ended "antes de comenzar" (before it began). He sums up the limbo perfectly: "ni novios ni amigos" (neither a couple nor friends), which feels "como morirnos y a la vez seguir vivos" (like dying and staying alive at the same time).
The hook is blunt and a bit dramatic, which is exactly why it works: "Destino, te odio" (Destiny, I hate you). He even cuts himself off once with "Destino, te-", as if he cannot finish the sentence.