A Routine Extravagance

[Wjames]

Like an old couple that always has sex on Thursday —
St. Patrick’s Day, New Years, and Birthdays
are limp obligations.

this almost  reads as a simili, personally i'd change [like] to [to]
other than that i like it for it's universal truthfulness that old people don't shag as much as they'd really want to if they could.

It was a simile, I dislike all the holidays where you're sort of forced to party (most probably disagree).