I know that people claim they make action before thought all the time in these situations but I am unconvinced.Of course he receives something from helping her, but that doesn't make the act selfish. An act can be altruistic even though there are elements of "selfishness" involved. In fact, I think its necessary. If he helped her against his good will, then the act would not be as altruistic as in the case in which he wanted to help her. Suppose one reluctantly plunges into the water to save a drowning baby not thinking of any consequential benefits whatsoever. It is absurd to consider this a less selfish act than wanting to rescue the baby because you wanted the baby to be rescued.
I think aperion made a very good point. It is remarkable how we seem to be wired to analyze such moral questions by reducing them down to the individual.
Memory of a person's exact thoughts is not easy to map out when interviewed and it is much more simple to say "I acted without thinking." "Acting without thinking" is well recieved and accepted but I don't buy it. I doubt the brain shuts off when approached with a life or death situation. There might be lightning fast decision making but still it's there.
The idea that motive is relevant to the concept of altruism versus selfishness is not absurd at all.