Tragando mis palabras literally means “swallowing my words,” but it is an idiomatic expression for having to take back or regret what you said. In the song, he feels embarrassed because he told everyone that this person was the one, and now their breakup makes him look like a liar.
“Los Alpes” follows someone left behind by a person who suddenly seems to have forgotten him. He wakes up and realizes she is no longer there, then spends the song waiting for answers and asking why she no longer looks at him “como antes” [the way she used to], when he felt like everything to her. The title points to a trip or dream they once shared: “Creo que ya nunca veremos los Alpes” [I think we will never see the Alps]. The Alps become a very specific reminder of a future that now feels impossible, especially because he connects that lost trip with never being seen by her again.
The speaker is also embarrassed by how completely he believed in the relationship. He told everyone “que eras tú” [that you were the one], and now he feels like a liar. His bluntest line is “Me dio la vida y me la destruyó” [She gave me life and destroyed it], a dramatic way of saying that this person once made him feel alive and now has left him devastated. He admits he would probably leave himself too if he were in her place, then says he is sober for the moment but will not stay that way because he misses her “mucho más que ayer” [much more than yesterday]. The soft “nana, nana” at the end leaves him suspended in that sadness, still waiting for an answer that never comes.