Singing Loudly

Etiquette question: is it proper to tell someone that their persistence in speaking of nothing other than the happy hours biglaw invite them to and how well they did their first semester of law school speaks nothing good of their character? It happens every time I go to lunch with this person. For awhile I was too nice to say anything because I thought she would get over it. Now the nice thing might be to tell her how annoying it is to make other people listen to nothing. At the least you could talk about the OC or American Idol, right? That would be somewhat more interesting.