It also depends on how long they have been trying. Did she say how long their sorority had been up and running? I may have missed that but if its only been like a semester or two...don't close down. You may want to try new ways of getting girls in, make your sorority a little more "appealing"-a sisterhood girls would want to join. I dunno...If you are not happy in it and you know that feeling wont change anytime soon...you know what you need to do
Good luck with whatever decision that is :