Me desvelo comes from the reflexive verb desvelarse, which means 'to stay awake all night' or 'to lose sleep'. It's a much more poetic and dramatic way of saying you can't sleep because something is on your mind.
In the song, the singer laments, "Me desvelo en las noches para pensar en ti" (I stay awake at night to think of you). This single word perfectly captures the feeling of a new, all-consuming crush that keeps you tossing and turning until the early hours.
Ever had a crush so big it takes over your whole life? That's exactly what Reik is singing about in "Qué Vida La Mía." The singer's entire day revolves around a girl he doesn't even know. He wakes up just to see her walk by, admitting, "Aún no sé tu nombre y ya eres dueña de mí" (I still don't know your name and you already own me). He spends his days imagining her laugh and his nights wide awake thinking about her. The title phrase, "Que vida, la mía" (What a life, mine), is repeated like a sigh, perfectly capturing that feeling of being stuck in a loop of daydreams.
He's desperate to make a move but doesn't know how, wishing he could just be the air around her. The chorus is his big, heartfelt plea. He starts by asking for something simple: "Solo quiero conversar, solo quiero conocerte" (I just want to talk, I just want to get to know you). But he quickly reveals how much he really wants, saying he's "muero por salir contigo" (dying to go out with you) and "muero por probar tus labios" (dying to taste your lips). It's a song about that intense, all-consuming crush from afar, and the hope that just one look or one signal could change everything.