"I started smiling because you were smiling"

What does it mean to be a good friend?
I had an interesting discussion with a very close friend last night. He's no longer on speaking terms with a mutual friend of ours. His reasoning was because she would not do him a simple favor. I asked what the favor was and he proceeded to tell me, ending with saying that he only wants friends he could count on.
Let me first say that the favor he was asking was indeed small, but seemed a little immaterial. I wasn't positive about why he would end such a great friendship with someone over something so silly.

I brought up the fact that he had forgot to wish me a happy birthday this last week. It was an important birthday being my 21st and all. I expected birthday wishes from him considering the closeness of our friendship. When he actually got around to remembering my birthday he just sort of dismissed it. It really hurt me a lot.

So my question for him was: Should I forgive you?
"It's up to you," says he with a small apology for forgetting my birthday.
But the real topic of the evening was: Maybe in order to have great friends, you should be one first.

I had a real hard time feeling sorry for him. He asked me to in turn do this "favor" for him. I obliged, but only because it meant a lot to him. Afterward I really contemplated some of my other friendships.
How often do we find ourselves in friendships with people where we feel like we care more for the individual than they care about us?
How often are other people in a situation where they feel they care more about me than I do them?
Do I show my friends the love they deserve? When something is important to them, do I come through?

It all boils down to this: Treat others the way you would like to be treated. I think the world could be a pretty bodacious place if people did that more often.