Dotty promised Joe that she would never divulge the secret that he told her.
That is the correct spelling of the verb "divulge" (reveal).
act of divulging, act of revealing, disclosure, exposure (Archaic)
The students were not willing to divulge the truth to the teachers. He would not divulge the names of his accomplices in the crime.
peter divulged all the information of his employer to the press.