Enfeitaram comes from the verb enfeitar, meaning to adorn or decorate. It's a beautiful and evocative word that paints a picture of something being made more beautiful or elaborate.
In the song, the lyrics mention "Frases que enfeitaram os meus sonhos" (Phrases that adorned my dreams). This suggests that the words from old letters once made the singer's dreams more vibrant and hopeful, highlighting a past joy now contrasted with present sadness.
"Quarto Negro" is pure heartbreak, Amado Batista style. It opens at dawn with a great line: amanhece o dia, solidão é fera (the day breaks, loneliness is a beast). Fera literally means a wild animal, and calling loneliness a fera says it bites. He is stuck neste quarto negro de saudade (in this black room of longing). Saudade is the famous Portuguese word for missing someone so much it aches, and here it fills a whole room.
The details are what make it sad. He rereads old letters, velhas cartas tão risonhas (old letters so full of smiles), and their words have faded, desbotaram todas com o pranto que chorei (they all faded with the tears I cried). His happy smile se desfez (came undone). Then the chorus turns into a wish: ah, se você me aparecesse de braços abertos pra voltar (oh, if you showed up with open arms to come back), he would hand over todo o amor que eu tenho pra lhe dar (all the love I have to give you) in one kiss.
It's a bit dramatic, sure, but that's the point. And it's great for learning the past tense: chorei, desfez, morreu, desbotaram.