Answer:She is Tom's mistress whom he is cheating on Daisy with Tom insists they get off the train in order for Nick to "meet [his] girl."
The only thing mentioned in the novel that Tom buys for Myrtle is the puppy. Myrtle herself buys the other things. The only Tom has given her is the puppy and pays for the apartment in the city, where the two of them meet for their affair.
Step-by-step explanation:
. Despite the fact that he is cheating, it is apparent that he doesn't love Myrtle more than he loves Daisy. ... If he loved Myrtle more, he would quickly clear up this misconception and marry her.