Azahar is the Spanish word for "orange blossom". It's a beautiful and poetic word that you won't hear in everyday conversation, making it a special addition to your vocabulary.
In the song, the singer's heart breaks as he sees the one he loves at the altar holding "flores de azahar" (orange blossoms). These flowers are a traditional symbol of purity and marriage, so this single word paints a vivid picture of the wedding scene that causes him so much pain.
Ever been so full of regret you do something a little crazy? This song is about a guy who shows up to his ex-girlfriend's wedding! He watches her walk down the aisle and can only think about how he messed everything up. He calls his own heart "Tonto, tonto mi corazón" (Foolish, foolish my heart) for not believing in her love back when they were together. His big mistake, he says, was his doubt: "Maldita mi duda, fue fatal" (My damned doubt, it was fatal), and it's what made him leave her.
Now, it's too late. As he watches her with her wedding flowers, or "flores de azahar," all he can do is "Llorar, llorar y llorar" (Cry, cry and cry). He's stuck remembering how perfect things were, "Contigo toqué el cielo" (With you, I touched the sky), while facing the reality that "ahora con otro te has de casar" (now you are marrying another). It's a classic cumbia soap opera about a huge mistake and the very public heartbreak that follows.