Nick is a Pushover

In my latest portion of The Great Gatsby,  the author, F. Scott Fitzgerald, uses an exchange between Nick, Tom, and Myrtle to indirectly characterize Nick.  He says "Hold on... I have to leave you here" when Tom tries drag him to the apartment with Myrtle.  However, Tom says "No you don't," and Myrtle says "Come on, I'll telephone my sister Catherine.  She's said to be very beautiful (p. 28)."  Nick doesn't have the courage to say no.  He could have easily made up an excuse about having to work or visit a friend, but he chose to go with Tom.  This was after he went with Tom to meet Myrtle even though he didn't want to.  Nick isn't even good friends with Tom.  They are really just acquaintances from college.  I think that Nick's inability to stand up to others might get him into trouble later in the book.  He might get mixed up with Tom's affair, or he might be involved with Gatsby somehow where he will do something that he doesn't want to do. This quality could even be a potential hubris.  For now, I haven't read far enough to know for sure, but I'm sure the rest of the story will reveal the answer.