Is It Possible to Treat Others How You Would Like to Be Treated?

In response to Shannon Ciuk's question, "Do you always treat others in a way that you would want to be treated?"...

     To be honest, no. In all actuality, I do not think anyone treats others how they would like to be treated. Situationally, there might be a few instances in which you refrain from acting in some way or stop yourself from saying something, for you realize you should be considerate. But, normally people act very rash, even if they try not to. For instance, imagine you are not on the best terms with your roommate. They have been waking you up in the middle of the night talking loudly on the phone, stealing your cereal, and snoring loudly at night. Essentially, little things are slowly adding up and making you angrier by the day. So, one day you come back from class and they start apologizing to you because they spilt nail polish on your rug. You loose it and scream at them. This is the natural reaction for many people given the circumstances, but imagine you are in the other person's shoes. They have been going through a very rough patch with their boyfriend and when he calls in the night, they get so worked up and forget that you are sleeping. They have no food left, and you had said at the beginning of the year that you would share, so they take a couple bowls of cereal. They have a really bad cold and that is why they have been snoring. As for the nail polish, that truly was an unfortunate accident. But, most people do not immediately think of all of these things. They only would think about how their roommate's actions are impacting them directly, not why the person is doing any of it.
     Basically, as much as people might try, it is very difficult to treat people how you want to be treated. In my above example, if you were the roommate, you would want the other to understand why you were doing what you were. Unfortunately, humans fight all the time because though they might deny it, they are all very self-centered. People care for one another, yet they always subconsciously have their own interests in mind. So no, I do not always treat people how I would like to be treated, but this is an unfortunate part of our nature. Do you think it is ever possible for someone to truly live selflessly, always putting others before their own, or will their own interests always take priority over that of others?