To add more possibilities to this growing list:
My German-Jewish mother's secular name was Jettchen (pronounced Yettchen), a diminutive of the nickname for Henrietta. (I won't go into what her "Hebrew" name was, as this would only add confusion).
However, no-one called her Jettchen; they used one of two other nicknames: Hette and Hetti.
I always thought that a nice Hebrew name to go with these would be Hadassah.
Brooklyn, New York, USA