The Rice University Neologisms Database

TFTI stands for “thanks for the invite”, and is used to indicate playful bitterness/sarcasm at the fact that one was actually not invited to a certain event. This is used when someone is looking at a picture on social media, or is part of a conversation in which a group is talking about something they did or somewhere they went and the individual was not invited/did not participate but wishes he could have been. Used as a funny comment and not a serious accusation, synonymous with the sentiment “I wish I could have been there” because the event looked like it was enjoyable.