I'm not sure why you believe that "high standards" and "fear of rejection" didn't exist a hundred years ago. Think Gatsby, from the Great Gatsby (published 1925): dude longed for human connection (hence throwing massive parties), but was terrified of being outed as not belonging to the social strata he found himself in. That's fear of rejection. People being to good for others is basis of the class system, and that predates written history.