Faustina was the daughter of consul Tiberius Claudius Severus Proculus and Plautia Servilla. Her paternal grandparents were Annia Aurelia Galeria Faustina and consul Gnaeus Claudius Severus Arabianus. Her maternal grandparents were Aurelia Fadilla and consul Marcus Peducaeus Plautius Quintillus.
Her grandfathers both came from families of consular or senatorial rank. Her grandmothers were full blooded-sisters and were daughters of Roman Emperor Marcus Aurelius and Roman Empress Faustina the Younger. She was a great-granddaughter of Marcus Aurelius and Faustina the Younger. According to surviving evidence, she seems to be the last known descendant of the Nervan-Antonian dynasty.
The first husband was Pomponius Bassus, a Roman politician. They married at an unknown date in the third century. Bassus’ father was probably Gaius Pomponius Bassus Terentianus, a suffect consul around 193. Bassus was consul in 211 and between 212-217 was a Legatus of Inferior or Superior Moesia.
Before June 221, the Roman Emperor Elagabalus desired Faustina to be his wife. Prior to Elagabalus marrying Faustina he ordered the execution of Faustina’s first husband. After Bassus’ death, Elagabalus forbade Faustina to mourn her husband. In July 221, Elagabalus married Faustina as his third wife. Roman society was more accepting of his marriage to Faustina than of his second marriage to vestal virgin Julia Aquilia Severa.
Elagabalus gave her the title of Augusta. According to numismatic evidence, she was known as Annia Faustina Augusta and added the Latin name Julia to her name. Numismatic and other evidence that have survived of her is from her second brief marriage to Elagabalus.
Elagabalus hoped Faustina would bear him an heir, instead of his maternal cousin Alexander Severus, to be his heir. Faustina and Elagabalus had no children. Towards the end of 221, Elagabalus ended his marriage to Faustina and divorced her. However, it is unknown why Elagabalus ended his marriage to Faustina. Elagabalus returned to Julia Aquilia Severa and married her as his fourth wife. It is unclear what happened to Faustina after her divorce from Elagabalus.