Despegar literally means "to take off" (like a plane) or "to detach." It's an interesting word because it implies a separation or a new beginning.
In the context of this song, the singer uses it in a more emotional sense, saying "sabes siendo despegar me enseñe mi punto débil" (you know, by detaching, you showed me my weak point). It suggests the pain of a breakup or emotional distance, where the act of
Julio Chaidez's "Golpes Bajos" is all about the pain of a breakup where one person isn't playing fair. Our singer is not happy because his ex is already seeing someone new, even though they were supposed to be taking time apart. He's really hurt, saying, "Me duele la enterarme que conociste a alguien más" [It hurts me to find out you met someone else] and then, to add insult to injury, she tells him she's already starting to love this new person!
He feels like she's hitting him with "golpes bajos" [low blows], attacking his weak spots. He even says, "Me enseñe mi punto débil y empezaste atacar" [I showed you my weak spot and you started to attack]. It's a really relatable feeling when someone you trusted uses your vulnerabilities against you. He's frustrated because they had an agreement, and she's not respecting it, making him feel like he's been cheated in this emotional game.