If you do something considerate for someone for which they have not asked, they are not obligated to notice or acknowledge said act, nor do they suffer from an obligation to return the kindness in any way.
In other words, there really are no brownie points for being a nice person? Why bother? What benefits accrue from from such behavior? When should you stop being thoughtful towards a person? Or people in general? At what point do you give up on an individual? When does the cost outweigh the benefit? Is the best strategy always to be cool and distant and only enter into situations which present a clear personal benefit?
Something to think about. This needs perspective.
...going back to sleep now...