Desgastando comes from the verb desgastar, meaning 'to wear down', 'to erode', or 'to exhaust'. It's a vivid word that describes a gradual process of deterioration.
In "Nos Perdimos," the lyrics say, "Y nos fuimos poco a poco desgastando," which translates to "And we slowly started wearing down." This word beautifully captures the slow, painful process of a relationship fading away, making it a poignant and memorable choice for the song's theme of lost love.
"Nos Perdimos" ("We Got Lost") is a heartbroken banda ballad about a couple who slowly drifted apart. The singer looks back and admits he didn't know how to love his partner the way she deserved, and little by little the two of them wore each other down until she gave up on him.
There's no anger in it, just regret. He remembers everything she gave him and wonders why he couldn't see what everyone else could see. By the time the chorus comes around, love has already slipped through his hands, and all that's left is missing her.
It's a classic breakup song for the genre: plain, direct words carried by a big banda arrangement, with the singer owning his part in how things ended.