“It is almost impossible to make jealousy go away in the heart and mind. However, it can be postponed for a while.”

Source: Gone with the Wind

Source: A Prayer for Owen Meany

Source: All About Love: New Visions

Source: Betting on the Muse: Poems and Stories

Tim Wheddon, Chapter 20, p. 265
Source: 2000s, Dear John (2006)

"Jubal Harshaw" in the first edition (1961); this is another line not in the "Uncut" edition of 1991 based on his original manuscripts, because this was one of the lines that Heinlein added, rather than trimmed down, during the editing process of the first edition.
Stranger in a Strange Land (1961; 1991)

Source: “L’illusion wagnérienne”, Portraits et souvenirs, Société d’édition artistique, 1899, 206‒220

All I Really Need to Know I Learned in Kindergarten (1986)
Context: There’s another thing not everyone figures out right away: It’s almost impossible to go through life all alone. We need to find our support group — family, friends, companion, therapy gatherings, team, church or whatever. The kindergarten admonition applies as long as we live: “When you go out into the world, hold hands and stick together.” It’s dangerous out there — lonely, too. Everyone needs someone. Some assembly is always required.

Source: What I Talk About When I Talk About Running