Hello! It looks like you are referring to characters from the novel The Great Gatsby. In the novel, we know that Tom is attracted to Myrtle Wilson. Although Tom and Mrs. Wilson carry on their affair happily, Mr. Wilson doesn't seem any the wiser. Catherine is Myrtle Wilson's sister. She tells Nick Carraway, the novel's narrator, that neither Myrtle nor Tom can stand who they are married to.
Catherine says that if it was up to her, she would not tolerate living with someone she could not endure being around. Catherine is adamant that if she were either Tom or Myrtle, she would have divorced the hated spouse and married the lover straight away. She tells Nick that the only reason Tom has not left Daisy to marry Myrtle Wilson is because Daisy is Catholic and does not believe in divorce. Catherine says emphatically that this is keeping Tom and Myrtle from marrying. Nick, however, is shocked at Catherine's deliberate lie; he knows that Daisy is not Catholic because Daisy is his cousin.