I did watched that movie a couple of times as a kid, but I have no idea how the name is.
It's a story about a Knight who had a girlfriend, The girl coulded transform to Hawk or Eagle during the day, and during the night she was a normal Human. Then she got hurt, and the Knight drag her to a Men in a Castle to take car of her. Then the dude went to revenge the bishop who hurt his girlfriend or wife, then or after he met a boy. Who helped him with the revenging the Bishop, who also the Boy was a Servent in the Castle, where the Bishop was living.

Ladyhawke maybe?

Thanks that is the movie looking for :)