I had been actually invited.
It’s interesting that Nick chooses to repeat this statement. By reiterating to the reader that he “had actually been invited,” Nick lets it be known that he is one of the elite few at the party, asserting his power over the other lesser guests.
He reassures not only the reader, but himself that he is wanted here and has come by choice, an option only those with high social mobility have. In a way, this simple fact confirms Nick’s status as a member of Old Wealth, at least in his mind.
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