Most ponies have relatively benign problems in their relationships. Small arguments, things like that. When the universe itself begins to meddle in Applejack's love life, both her and Rainbow realize it isn't going to be as easy as they thought.
Principal Celestia always has wings in her dreams. So when a magical clash in front of her school sets her phantom wings to itching, her life turns upside down. And she hasn't even heard about Equestria yet.
Anyone who has sought counsel from Princess Celestia has met Raven, her most faithful aide. She has been a veritable second shadow to the princess for as long as the castle staff can remember... longer than they can remember, in fact. Much longer.
In a steampunk reimagining of the universe, Twilight Sparkle finds perhaps the one pony as lonely as she is. It's rather unfortunate that they're on the moon.