When one's life is so despairingly bad. The expression “vale of tears” goes back to pious sentiments that consider life on earth to be a series of sorrows to be left behind when we go on to a better world in Heaven. It conjures up an image of a suffering traveler laboring through a valley (“vale” ) of troubles and sorrow. “Veil of tears” is poetic sounding, but it’s a mistake.
"Frank's life is such a vale of tears" said Charlottle. Everyone solemnly agreed.