*Note: Something like this may have been posted here before, but here are my thoughts on it. Longest forum post, away:
I was just listening to the new Everfree Radio episode (the one released with the Baby Cakes episode), and they brought up a theory of Pinkie Pie having self-confidence issues. This really grabbed my attention. It's much more likely that she suffers from some repressed self-worth issues rather than her being the crazy/psychotic "Pinkamena Diane Pie."
Honestly, I agree with that idea. It would explain why she's CONSTANTLY happy in her every appearance. Granted it might just be how she is, that kind of over-the-top happiness is usually the sign of something deeper going on. Those who suffer from self-confidence issues or depression (sadness) want people to think that they don't, so they throw on a mask to hide it. Her displays of constant happiness and joy could just be a coping mechanism for her.
Two episodes back this theory a bit. In Party of One, the cause of Pinkie's depression was because of her assumption that her friends did not like her or her parties anymore. Her insecurities cause her to jump to that conclusion. Let’s assume that those insecurities stemed from her days as a filly. One of Pinkie’s first friends could have gotten so annoyed by her that they just abandoned her (much like the events in Party of One). She reacted with a surge of intense sadness, seeing as how bad things can still happen despite her new lease on life (Cutie Mark Chronicles). Her new motto of “Happy happy, party party” kicked in and she decided to repress that inner sadness with an even more intense outward display of happiness. After feeling a bit less sad internally, she adopted a habit of dealing with drawbacks by going overboard with false happiness.
The second episode is the more recent one, Baby Cakes. However, this example deals with more self-confidence than sadness. In the episode, Pinkie is in way over her head when she decides to take the responsibility of watching after two hyper-active foals. All of her attempts at calming them and keeping to a schedule seem to fail one after the other. It isn’t until Twilight Sparkle comes to the door with the intention on helping Pinkie with the foals that things begin to change. Twilight mentions how “some ponies just aren’t able to handle that kind of responsibility.” Pinkie takes offense to the statement and promptly kicks Twilight out, stating to herself that she can handle things on her own. She then goes back up to the foals and suddenly “lays down the law” in a stern manner. This is where the problem comes in. People with self-confidence/self-worth issues either think: A) They aren’t good enough for anything, or B ) They constantly have to prove/validate themselves to show others that they are competent. In this case, Pinkie clearly falls under the latter.
All of this is more of speculation than fact, but I feel that there’s some pretty solid proof that Pinkie isn’t really the happy and bubbly pony that she appears to be. I’d love to hear your thoughts on the matter.
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To those that made it all the way to the end of this, your cookie will be in the mail and delivered promptly, provided that Derpy Hooves doesn’t mess up the shipping and sends them back to me. In which case, I shall eat every last one of them.