Quote from Phoebe in The One with Monica and Chandler's Wedding (Part 1)
Rachel: Maybe it's not what we think. Maybe it's "Tell Monica I'm sorry I drank the last of the milk." Phoebe: Or maybe he was writing to tell her that he's changed his name, you know. "Tell Monica, I'm Sorry." Ross: I think it means he freaked out and left. Phoebe: Don't be so negative. Good God, isn't it possible that "Sorry" is sitting in there right now?