What's love got to do with it?

          Some people could argue that it is possible for someone to be truly altruistic, but I'm not one of them. I don't even mean that in the cynical way that I sometimes approach other topics like this--this rings truer and sits better with me than a lot of other things I've been researching--but I don't believe that true altruism can be achieved... anymore. (This obviously isn't a new concept, but in terms of my own beliefs and opinions it is relatively new, so I'm very open to discussion.)

I offer, on me let thine anger fall;
Account me man; I for his sake will leave
Thy bosom, and this glory next to thee
Freely put off, and for him lastly die.

          This excerpt is found in lines 237-240 in Book III of Paradise Lost. It is spoken by the man who I believe committed the last truly altruistic acts on earth: Christ. Christ was perfect and everything that he did he did for God and for us. He did it with a pure heart. When he offered himself to this task to atone for our sins, his language is a tell that he is doing it for anybody but himself.
          Here's how I feel...people do good things every day. We all serve and we all do these little acts of kindness just because we know it will make the other person feel better. We even go so far as to not expect any sort of reciprocation or reward for good behavior. I would have assumed that this is altruism, but even if one doesn't expect something in return, one can still get the good feeling of knowing one did something for someone else...which is a benefit--not intentional--but a benefit nonetheless. That person still got something for themselves out of what they thought was a selfless act, and I believe that makes it impossible for the act to be truly altruistic.