Jamás translates to "never" or "never ever," but it carries a stronger, more definitive sense of finality than the more common "nunca."
In "Duele," the word is used to emphasize the pain of a permanent loss. The lyrics "Que te lleves mis recuerdos de viaje a nunca jamás" (That you take my memories on a trip to never ever) and "como si este amor nunca existió jamás" (as if this love never ever existed) highlight the absolute and irreversible nature of the heartbreak, making it a poignant and memorable choice.
Dama's song "Duele" is all about the intense pain of a breakup. The singer is heartbroken that their love is leaving their life "sin más" [without further ado], taking all their memories on a trip to "nunca jamás" [neverland]. It hurts so much not to have them there, and it's agonizing to watch the train of memories depart. The thought of never kissing them again is truly painful.
He can't believe how this happened, especially since just looking at each other used to stop time and passion would take over. Now, the ex wants to offer just friendship, asking him to look at them as if their love never existed. He bluntly says, "Estás loco, eso nunca lo verás" [You're crazy, you'll never see that]. Even though his heart is broken, he knows that "siempre amanece, todo pasará" [the sun always rises, everything will pass].