There never has to be a reason to have lunch with the ladies other than to visit. I make it a point to gather a few girls every 4 to 8 weeks to my home to eat, have a glass of wine and enjoy a meal. While it would be much easier to meet at a local restaurant, it's just not the same.
Creating a menu and an intimate ambiance is something that can not be done in a public place. But in your home, you can create any atmosphere you dream up.