Question: What American singer and actress had a love affair with Nelson Eddy?

Context articles: Hercules and Love Affair (album)
Sharon Rich
Jeanette MacDonald
Sweethearts (book)
Gale Sherwood
A Prussian Love Story
Jo &amp; Friends
Rough Town
Edouard Lippé
Northwest Outpost

Hercules and Love Affair is the debut studio album by American electronic music band Hercules and Love Affair, released on March 10, 2008 by DFA Records.
 The album was produced by Andrew Butler and Tim Goldsworthy.
 Andrew Raposo (of fellow DFA band Automato) and Tyler Pope (of !!!
) contributed bass to the album, while Antony Hegarty co-wrote and performed vocals on select songs.
Sharon Rich (born June 11, 1953) is an author and film historian, best known for the biography "Sweethearts" about 1930s singing stars Jeanette MacDonald and Nelson Eddy.
 She was close friends for many years with Jeanette's older sister, actress Blossom Rock (aka Marie Blake).
 Along with interviewing hundreds of people, Rich had access to many collections of private letters, Eddy’s personal scrapbooks, diary entries, FBI files and MacDonald’s unpublished autobiography.
 As follow up documentation to "Sweethearts", Rich has written several additional books and edited and written over seventy magazine articles.
 In 1995 she was awarded a Dame of Merit by the Knights of Malta for her contribution to History and Literature.
Jeanette Anna MacDonald (June 18, 1903 – January 14, 1965) was an American singer and actress best remembered for her musical films of the 1930s with Maurice Chevalier ("The Love Parade", "Love Me Tonight", "The Merry Widow" and "One Hour With You") and Nelson Eddy ("Naughty Marietta", "Rose-Marie", and "Maytime").
 During the 1930s and 1940s she starred in 29 feature films, four nominated for Best Picture Oscars ("The Love Parade", "One Hour with You", "Naughty Marietta" and "San Francisco"), and recorded extensively, earning three gold records.
 She later appeared in opera, concerts, radio, and television.
 MacDonald was one of the most influential sopranos of the 20th century, introducing opera to movie-going audiences and inspiring a generation of singers.
Sweethearts: The Timeless Love Affair On screen and Off Between Jeanette MacDonald and Nelson Eddy is biographical book by Sharon Rich.
 First published in hardback in 1994 by Donald I. Fine, Inc., the book covers the relationship of Jeanette MacDonald and Nelson Eddy.
 Rich drew heavily on Eddy's mother, who had kept Eddy's diaries and letters.
Gale Sherwood (born March 4, 1929) was a Canadian singer and actress, born Jacqueline Nash, who is best known as the singing partner of Nelson Eddy from 1953 until his death in 1967.
A Prussian Love Story (German: Preußische Liebesgeschichte) is a 1938 German historical romance film directed by Paul Martin and starring Karl Günther, Hans Nielsen and Willy Fritsch.
 The film depicts the love affair between William I and Elisa Radziwill.
 In the Third Reich the film was banned right after completion because the love affair of Joseph Goebbels and the actress Lída Baarová had become public—it was first shown in 1950.
Jo & Friends is a 2000 compilation album of songs recorded by American singer Jo Stafford and various other artists.
 The friends who accompany her on this album include Nelson Eddy, Liberace and Vic Damone.
 It was released by Sony Music on their Sony Music Special Products label on January 1, 2000.
 A second album, titled "Jo Stafford and Friends" featuring the same tracks was released on October 30, 2007, on the Collectables Records label.
Rough Town is a 1994 album recorded by French singer Johnny Hallyday.
 It is entirely written in English-language to win over the anglophone countries.
 It was released in September 1994 and achieved success in France, where it debuted at the top of the charts on October 2, 1994, but dropped just after and stayed for nine weeks on the chart (top 50).
 It provided two singles in France, "I Wanna Make Love To You" (#18) and "Love Affair" (#35), a duet with Kathy Mattea.
 The album was also released in Germany, but was unsuccessful in this country.
 The video for "Love Affair" was directed by Dani Jacobs, filmed in Nashville and features Johnny and Kathy Mattea who duets on this track.
Edouard Lippé (May 24, 1884 in Pennsylvania – 1956) also frequently spelt Eduardo Lippe.
 American composer, baritone and singing teacher.
 His major title to fame nowadays rests on the fact that he was baritone Nelson Eddy's first and principal teacher, apparently even financing his pupil's finishing studies in Paris and Dresden.
 Lippé followed Eddy to Hollywood, where he appeared in the small role of the Landlord in the 1935 film version of Victor Herbert's "Naughty Marietta".
 He was also the singing teacher of Todd Duncan, George Gershwin's personal choice for Porgy at the world première of "Porgy and Bess", and one of the first African-American opera singers of renown.
 Dr. Lippe, as he was also known, also gave lessons to another lesser known but gifted young singer by the name of Victor Marchese who went on to record with MGM records - see Flamingo.
 Lippé wrote many songs, including a particularly graceful setting of Elizabeth Barrett Browning's "How Do I Love Thee?"
 included by Arleen Augér in a 1986 recital of love songs.
Northwest Outpost (also known as End of the Rainbow) is a 1947 American musical film directed by Allan Dwan and starring Nelson Eddy, Ilona Massey and Joseph Schildkraut.
 The film was Eddy's last, and is an operetta film like his previous starring roles.
 He was persuaded to make it by Republic Pictures because Rudolf Friml was writing the score.
 It was well received by critics and had a strong box office performance.