Audrey of Ely (ca. 636–679), or Æthelthryth, or Ethelreda, or Æðelþryð (my favorite), was one of the four abbey-founding daughters, all saints, of King Anna of East Anglia. From her youth she was devoted to prayer, the blessed sacrament, and works of mercy, not to mention piety, purity, and humility. She felt a strong call to the cloister, but her calling wasn’t her call. She was married at about fourteen to Tondberct, head honcho of the South Gyrwe, the swamp-people of the Fens. One can imagine her leaving her father’s castle for mosquito country, little cheered by the fact that her sister Sexburga (Jul 6) had married a real king who lived on solid ground. Tondberct was a devout guy, and was willing to live in chastity, although it may have killed him—he died within three years of their nuptials. Fortunately for Audrey he had given her the island of Ely as a morning gift (dower, not to be confused with dowry which is given to the bride’s parents), so she repaired there.
She had little time to settle in, though, as she was again married off, this time to Ecgfrith of Northumbria, at the time a mere lad. They lived as brother and sister for some time, as she taught him the catechism, directed his spiritual growth, and in general worked at inculcating in him the idea that their marriage should remain chaste. After twelve years of this, Ecgfrith thought the time had come to—well, you know. Audrey sought release from the marriage from Wilfrid, Bishop of York, who gave her the nod and sent her to the Benedictines at Coldingham (where food lasted longer than at Warmingham). There she took the veil.
Ecgfrith, less than fully delighted with this turn of events, tried to convince Wilfrid to put the screws on Audrey (if you’ll excuse the expression). Wilfrid remained adamant, and for his trouble he was ultimately deposed. (But that was years later and this isn’t his story.) Ecgfrith hurried to Coldingham, intending to drag Audrey from the cloister by brute force. The brute. She learned of his approach, however, and slipped out the back door. Along the way she stopped overnight at Stow, thrusting her staff into the ground to wait for her till morning. When she arose, it had grown into an ash tree, and in time a church dedicated to her sprang up on the site. This is one of the many places to bear her name—judging by church names and calendar entries, she is the most popular female Anglo-Saxon saint.
She made it safe to Ely, but Ecgfrith was hot on her tail (so to speak). He either sent or led an attempt to invade the island by boat, but an unusually high (and long-lived) tide sprang up (or washed up or whatever it is tides do), and they could not land for seven days. He gave up, went home, and married somebody else.
Audrey founded a double abbey on Ely, and served as its first abbess. Sometime after her death (from a presumably-cancerous growth on her neck which she took to be a punishment for wearing too many fancy necklaces in her youth), her sister (q.v.) exhumed her incorrupt body (nasty growth quite gone) and placed it in a lovely marble tomb. The monastery was destroyed by the Vikings in the ninth century. A fair was held on her feast day, though, which became famous for “St. Audrey’s lace,” necklaces (or ribbons) pitched as cures for neck/throat ailments. This became shortened to “tawdry lace,” then “tawdry,” which came to mean “cheap, showy, gaudy” as over the long centuries the QA deteriorated.
Audrey is the patron of widows, of persons with neck and throat ailments, and (I’m sure this is unrelated to the other two) of the University of Cambridge.
 Please note that the East Anglian Medical Association did not endorse these claims.