The couplet of the sonnet consists of lines 13 and 14, and they seem to be used to clinch the sonnets ending. it offers the compensation as all woes vanish in recollection of the "dear friend". The narrator talks as if the joy of the dear friend wipes out all the pain of remembrance.
When someone makes reference to a familiar story or cultural reference, such as Ulysses and Achilles from Homer's "The Odyssey", it is considered an allusion.
