It seems to me that when vanity comes into love it can only be because really you love yourself best. After all, it constantly happens that a man when he's married falls in love with somebody else
 W. Somerset Maugham, The Moon and Sixpence (1919). copy citation

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Author W. Somerset Maugham
Source The Moon and Sixpence
Topic vanity love
Date 1919
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/222/222-h/222-h.htm

Context

“I'm not the sort of man that women love. I've always known that. I can't blame her if she's fallen in love with Strickland." "You certainly have less vanity than any man I've ever known," I said. "I love her so much better than myself. It seems to me that when vanity comes into love it can only be because really you love yourself best. After all, it constantly happens that a man when he's married falls in love with somebody else; when he gets over it he returns to his wife, and she takes him back, and everyone thinks it very natural. Why should it be different with women?" "I dare say that's logical," I smiled, "but most men are made differently, and they can't."” source