Atormenta comes from the verb atormentar, meaning 'to torment' or 'to plague'. It's a strong, evocative word that conveys deep emotional distress.
In "Cuando Volverás", the singer uses atormenta to express the intense pain and anguish he feels at the thought of his beloved being with someone else: "Y el pensar que estás con otro me atormenta cada día más" (And the thought that you are with another torments me more each day). This word perfectly captures the song's theme of heartbreak and longing.
If you want pure, dramatic bachata heartbreak, this track by Aventura is the ultimate place to start. The whole track is a desperate plea to a partner who vanished out of thin air. He explains that she left one morning without giving a reason, without even leaving a little note or a clue: "Se fue una mañanita sin motivos / Sin dejarme una cartita, ni una seña de adonde estará" (She left one morning for no reason / Without leaving me a little letter, nor a sign of where she will be). He is not handling it well at all. He stops eating and sleeping, crying out, "Ya no como, ya no duermo esperando tu regreso" (I don't eat anymore, I don't sleep anymore waiting for your return). It gets so over the top that he even asks someone to call a doctor because his chest hurts from so much sorrow.
What makes the track so catchy is the relentless repetition of the central question: "¿Cuándo volverás?" (When will you return?). Alongside the sorrow, jealousy creeps in. He admits that imagining her with another man is tearing him apart ("el pensar que estás con otro me atormenta"). Throughout the chorus and verses, he showers her with affectionate nicknames common in Dominican Spanish, calling her "mami" (babe), "morena" (brunette or dark-haired/dark-skinned woman), "mi reina" (my queen), and even "chichi" (baby). It is frantic, dramatic, and packed with everyday terms of endearment that show just how much he misses her.