It is cruel enough to suspect that a rival is loved, but there is no doubt that to hear the woman one adores confess in detail the love which rivals inspires, is the utmost limit of anguish.
 Stendhal, The Red and the Black (1830). copy citation

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Author Stendhal
Source The Red and the Black
Topic love doubt
Date 1830
Language English
Reference
Note Translated by Horace B. Samuel
Weblink https://en.wikisource.org/wiki/The_Red_and_the_Black

Context

“He saw that she was portraying what she had in her mind's eye. He had the pain of noticing that as she spoke she made new discoveries in her own heart. The unhappiness of jealousy could not be carried further. It is cruel enough to suspect that a rival is loved, but there is no doubt that to hear the woman one adores confess in detail the love which rivals inspires, is the utmost limit of anguish. Oh, how great a punishment was there now for those impulses of pride which had induced Julien to place himself as superior to the Caylus and the Croisenois! How deeply did he feel his own unhappiness as he exaggerated to himself their most petty advantages.” source