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Thranduil promotes Tauriel to a Captain of the Guard, telling her that this new position means less time in combat and more time commanding others into battle.
Not one to avoid a fight, Tauriel charges into battle first anyways.
After the battle Thranduil summons her, but when she tries to give her opinion on what they should do next Thranduil tells her that he saw her fighting depsite his orders and doesn't know why he should trust her opinion if he cannot trust her. He admits she fought bravely, but forbids it from happening again.
Later, while in a meeting interrogating an intruder, Thranduil is brought the news that Tauriel disappeared into the forest after hearing someone calling for help.
When she returns he strips her of all rank and tells her she is no longer welcome amongst his soldiers at all.
When the big battle comes Tauriel and Thranduil come face to face on the battlefield and she threatens him with her bow, saying he cares for no one but himself. Furious, Thranduil strikes out at her, breaking her weapon.
Tauriel collapses wondering what she ever did to make him send her away. When she asks why, Thranduil admits it is because he cares for her and couldn't bear to watch her fall in battle like his first wife.