What did Tom reveal that caused Daisy to choose him over Gatsby?

Even though we can see that Daisy is composed of Gatsby's ideals, we can also see her other side. She is a sweet, charming and beautiful woman but also she is in love with money and material luxury (same as Tom) which is bringing her to one shallow and boring life. Daisy is one aristocratic East Egg woman that is representing all of the amoral values. In Chapter 7 she is choosing Tom over Gatsby and that is where her true nature is coming out. After that, she is allowing Gatsby to take all the blame for killing the woman that she killed when she was driving his car. She did not even go to Gatsby's funeral when that happened, Tom and Daisy had moved out.