1. "My wine-of-the-month club needs you."
A good compliment should be like a good gift: thoughtful, easy and specific to the recipient. So tell her: "You chose the best Bordeaux the last time we went to dinner" or "You have a way of getting everyone to get along." Whatever it is, remind her of the non-mom-related wonderful thing about her that makes your wine-tasting club (and/or the world) a better place for her presence.