Scene from Blade Runner

A scene that confused me was when Roy saved Deckard. They fight for twenty minutes and then Deckard is so close to dying and Roy pulls him up by the arm after breaking his fingers five minutes prior. Then Roy pulls the dove out of no where and it flies off into the blue sky. Its real nice of Roy to save Deckard I just thought it was weird. The ending of this movie is not what I expected at all. I need to watch it again so I can pay more attention to detail and notice things that I did not notice before.