What does Fitzgerald's last line of the novel mean?

In The Great Gatsby, the last sentence reads: So we beat on, boats against the current, borne back ceaselessly into the past. This refers to the dualities of Gatsby and America.  Gatsby looked like a Romantic hero to Nick: he was a self-made man, a rags to riches story, a symbol of the American dream.

Explanation:

a pirate walks into a bar with a steering wheel sticking out of his pants.

bartender: isn't that uncomfortable?

pirate: arrgh! it's drivin' me nuts!

the tone of the passage is sympathetic to the forbidden love of romeo and juliet. the nurse plays a significant role in the play. she is responsible for making their meeting again possible. additionally, there is a sense of warning in the choice of words of the nurse. she seems to be authoritative when she calls romeo "scurvy knave", and at the same time the fact that she addresses to him as "sir" reflects respect. the nurse is "vexed", this word describes her confused state of mind. on the one hand, she finds romeo a fine and eloquent man, but on the other, it is thought that man's nature forces men to try to trick women.