She served as lady-in-waiting to the English queen Anne of Denmark.
She was the sister of Robert Devereux, 2nd Earl of Essex, and is traditionally thought to be the inspiration for "Stella" of Sir Philip Sidney's Astrophel and Stella sonnet sequence (published posthumously in 1591).
She married Robert Rich, 3rd Baron Rich (later 1st Earl of Warwick) and had a public liaison with Charles Blount, Baron Mountjoy, whom she married in an unlicensed ceremony following her divorce from Rich.