Ahogan comes from the verb ahogar, which means to drown. It's a strong and evocative verb that paints a vivid picture of being overwhelmed.
In the song, Luciano Pereyra uses ahogan metaphorically when he sings, "Si me ahogan tus recuerdos cada tarde de domingo" (If your memories drown me every Sunday afternoon). He's expressing how intensely he's consumed by his memories, feeling as though they are suffocating him, making it a powerful and memorable word choice.
"Si Fuera Tan Fácil" ["If It Were So Easy"] is Luciano Pereyra arguing with himself for three and a half minutes. He tells himself "Olvidemos lo nuestro" ["Let's forget about ours"], repeating advice a stranger gave him about moving on, and then admits none of it worked. Every instruction in the song turns out to be something someone else said to him, not something he actually believes.
The line that gives the song away is small: "O el café de la mañana, por la plaza de Luján" ["Or morning coffee, through the Plaza de Luján"]. It's not a big confession, just a street and a cup of coffee, and that's exactly why it lands harder than the chorus around it. By the time he's said "Juro te habría olvidado" ["I swear I would have forgotten you"] for the fifth or sixth time, it stops sounding like a promise and starts sounding like a man trying to talk himself into something he can't actually pull off.