Constantius married her in
Antioch in 361, after the death of his second wife,
Eusebia in 360. Ammianus simply reports that the marriage took place while Constantius was wintering in
Antioch, taking a break from the ongoing
Roman–Persian Wars. "At that same time Constantius took to wife Faustina, having long since lost Eusebia". She was pregnant when Constantius died on 3 November 361 and later gave birth to their posthumous daughter,
Constantia, the only child of the emperor. Constantia later married Emperor
Gratian. ==Widow==