“She’s been talking about it for ten years.” He rested for a moment against the pump, shading his eyes. “And now she’s going whether she wants to or not. I’m going to get her away.”
This strongly implies that Wilson knows Myrtle is seeing someone else. That is the reason he and Myrtle are moving West, to make sure she won’t see this “mystery” man. Even though that man is actually the person Wislon is talking to (Tom).
To help improve the meaning of these lyrics, visit “The Great Gatsby (Chapter VII)” by F. Scott Fitzgerald and leave a comment on the lyrics box