I have a co-worker (who I used to consider a friend until she kept doing this) who thinks it's hilarious to come up to me once or so a week with her lunch that consists of things she knows I can't have and go "Mmmmmmm this is going to be sooooo good". Yesterday I said "Is it pizza.... you know something I can't have?" and she goes "Yup - yummy!" and proceeds to tell me everything that's on it and how delicious the crust is. It's so rude and I don't even know how to respond without going crazy.