Desprende-te is the imperative form of the verb desprender-se, meaning "to detach oneself" or "to break free". It's a less common, more evocative verb than simply saying "let go".
In the song, Valas uses this word to urge the listener to "desprende-te do passado" (detach yourself from the past). It's a powerful call to action, encouraging self-reflection and personal growth, making it a memorable and impactful word in the lyrics.
Valas builds 'Terapia' around a single idea: a relationship that works better than an actual therapist. He opens with a specific memory, not a vague one: 'Lembro-me como dançavas agarrada a mim' ('I remember how you danced holding onto me'), then gets to the hook, 'Na tua terapia, ficava tão colado' ('In your therapy, I'd be so glued'). Wrapped up in someone's arms, every other problem just resolves itself.
Halfway through, the mood shifts from that memory to his own doubts about whether he's actually going anywhere. He asks himself if he 'cortei a fita na meta' (cut the ribbon at the finish line) or just talked a good game, then tells himself to quit dreaming from his bedroom and actually move. The closing line answers the question: 'Eu durmo com a musa na cama da música' (I sleep with the muse in music's bed). Writing songs is the other therapy, the one that's always open.