I just spent some time looking through
her selfie tag.
And honestly I don't see how she can be a doll at this point. There are gifs with her eyebrows moving, and all sorts of stuff including her wearing that outfit with the mask we saw in the weird vine. However, everything seems really photoshopped. As for why she posts so many pictures despite having body issues, this happens for a lot of girls. Girls like to take pictures of themselves looking nice to feel better.
At this point that's all I can say for sure. Something fucked up is happening, but I'm not sure it's about a doll.