Gosh I hate this theory. I hope it burns in the lava of Mustafar.
As for my Star Wars theories, I truly believe Rey is Luke's daughter. The facial similarities are there, and in the credits for the Force Awakens, Luke's theme blends nicely before Rey's theme. In fact they intertwine more perfectly than any other music.
Plus, Kathleen Kennedy, the current head of Lucasfilm, already said that this new trilogy would "focus on a Skywalker." That leads me to believe Rey is the daughter of Luke, and that Kylo Ren is her cousin.