As quite a Chatty Cathy myself sometimes, please give her another chance. In a new group, she may have felt the need to introduce herself and let y'all know what she is about. It's hard being the new kid to a bunch friends who are already acquainted. If she still dominates the conversation after a few visits, I think the lunch idea is terrific. It also makes a difference if she is "dumping on y'all" or just telling more info than you want to know.