Dress as the beloved Gandalf wizard and the ethereal Galadriel, Lady of Lothlórien.
While it is true, the rightful male to stand beside Galadriel would be her husband, Lord Celeborn, those of us who love Lord of the Rings and The Hobbit recognize the bond between Gandalf and Galadriel. Therefore, they would make great couple costumes for a Halloween party.
The Deluxe Gandalf Costume
The deluxe Gandalf costume includes the robe, the hat, the belt and the satchel. However, you would still need to buy the wig and beard separately.
The Galadriel costume includes the gown and the headpiece. The dress is great, but the crown is not the best. I would recommend purchasing a more substantial crown to go with the gown. Plus, there may several other accessories you might want to consider like Elf ears or a wig, but the outfit would suffice as is.
Because the crown is so extremely important to the overall beauty of the costume, I would recommend purchasing an alternate crown. The crown that is included with the dress is flimsy and not really suitable for Galadriel.
This crown is not perfect, but it is better made and overall, I believe you will be much happier with this headpiece. However, do keep in mind that it is a costume crown and not the higher quality of fashion jewelry.
The Scene Where Galadriel Saves Gandalf in The Hobbit: The Battle of the Five Armies