Good Friend.
In my opinion good friend, is a friend, whom you can trust and believe in each sentence, being with him in different situations and e.t.c.
However, "good friend" means that his shoulder is always nearby, and you can be always protected.
Although, good friend is the way you are in psychological way, because he can mAke you happy or can be sad, if you are so.
To sum up, I would like to tell, that everyone should have such a good friend, because you don't know what can happen, so you need a support.