I think you're asking about the dinner at Daisy and Tom's house in chapter one. This scene helps the reader to understand Daisy and Tom's marriage before Gatsby is in the picture and shows us that Daisy is generally dissatisfied with her life.
She begins by pointing out that Tom has bruised her little finger and that he is a "brute of a man." This alludes to the possibility that Tom is abusive toward Daisy. Though she says he didn't mean to hurt her, she feels the need to point it out to her dinner guests, Nick and Jordan. Tom shows himself to be abusive later in the book, when he breaks Myrtle's nose, so there is the possibility he has also physically abused Daisy.
When Tom begins discussing a racist book he has read, Daisy responds with a sarcastic comment that shows she disagrees with his views, though doesn't intend to challenge him directly. This could indicate that issues are not openly discussed in their marriage, probably because Tom believes himself to be correct in all things and Daisy has resigned herself to not fighting him.
When Tom's mistress, Myrtle, calls during dinner, Daisy first attempts to keep the conversation going outside, but finds herself irresistibly drawn inside to Tom, where a "subdued, impassioned murmur" is heard before Tom and Daisy return. Daisy gives an excuse with "tense gayety," showing she is upset but trying to hide it from her guests.
Finally, during a private conversation with Nick after dinner, Daisy admits that she's "pretty cynical about everything" and that she thinks "everything's terrible anyhow."
It's clear from this scene in chapter one that Daisy is unhappy with her life. It's possible that Daisy's internal conflict is whether or not to leave her husband. However, from her resignation where Tom is concerned and her focus on money, it seems unlikely that Daisy is actually considering that as an option at this point. It isn't until she reunites with Gatsby, who could make her happy and wealthy, that leaving Tom actually becomes a possibility for Daisy.