I cant remember the ame of this movie :(?

so its a futuristic movie and like all i remember s that this guy who lives in a big city meets a girl from out side the city, which is all desert, and he leaves his old life andhis wife to run away with her. At the end of the movie they some how crashes the car while running from authorities and he loses his memory and is retruned to his old life. The last scene is of the girl walking through the desert alone. Thats all i remember :(