Edward Frederick Brewtnall
Most older Sleeping Beauty tales did not have a slighted fairy who was not invited to a party; the Princess' fate was foretold but she was not spitefully cursed. It wasn't until Perrault's tale that the motif became associated with the tale. Perrault came from a world of class distinctions and court manners. In many cases he poked fun at the aristocracy in his tales. Given his propensity for satire, I wouldn't be surprised if he didn't mean for the fairy's motivation to be taken so seriously.
Yet, the slighted fairy is not completely without precedent. From Kate Forsyth:
"The uninvited fairy motif goes back to Greek mythology when he goddess Eris is not invited to a wedding, but arrives anyway, and throws the Golden Apple of Discord amongst the other goddesses with the inscription ‘For the Fairest’ which causes an argument over whom should claim it, and leads to the Trojan War."
in "chanson de geste Les Prouesses et faitz du noble Huon de Bordeaux: the elf-king Oberon appears only dwarfish in height, and explains to Huon that an angry fairy cursed him to that size at his christening."
Yet these instances aren't from Sleeping Beauty tales. In one variant, The Glass Coffin, the curse was given by a traveler who was offended when the beautiful girl wouldn't marry him.
And despite its likely tongue-in-cheek flavor from Perrault, the idea of being rejected by society or left out by your friends is still not something to take lightly. What comes to your mind when you read the episode of the uninvited fairy?