Silly question, but these are the things that keep us brides-to-be up at night! I am having a rubber calligraphy stamp made to use on our invitation and RSVP envelopes. I typically go by a version of my formal name (for example Mandy instead of Amanda), and FI goes by a shorter version of his formal name (such as Chris instead of Christopher). In the invites themselve we are using our full formal names. I am just curious if I should use the full spelling of our names for the return address as well or if I can use the names we are better known as. I'm pretty sure it should be our formal names, but just want to ask around.