This St. Gregory was the younger brother of St. Basil the Great and the good friend of St. Gregory of Nanzienzen. He was a disillusioned professor of rhetoric who may or may not have stayed with his wife, Theosebeia, after he became a monk, hermit, and then the Bishop of Nyssa (Lower Armenia). Although the second ecumenical council at Constantinople called him Father of the Fathers for his standing among the defenders of orthodoxy (against heresies like Arianism and Meletianism), he had been deposed for a couple years because of his inefficient administration of his diocese.
"Easy-going, tactless, and inefficient..." is how one source describes him. I can relate.