According to TV tropes, under "Misaimed Fandom":

"Frozen's Signature Song, Let It Go, is considered by many fans to be an empowerment theme, with LGBT fans specifically describing it as Elsa's coming out of the closet moment. In actuality, Elsa is running away from and forgetting about her responsibilities as queen to hide out in the mountains all by herself. She is being open about who she really is, but only after making sure no one else is around her, and when Anna comes to find her Elsa almost immediately panics and forces her to leave."