I think this guy is right

When i listen to this song, i definately get the feeling that he's singing about suicide, but not a sudden one, rather one that's been long and drawn out. I see a person suffering from depression before finally taking his or her own life. I think that's what he means by "sometimes goodbye's the only way". The person comitting suicide sees their death as the only way out. "The sun will set for you", i think, is a refrence to how the sunset is the end of the day, thus a sunset would be the end of their life. I think the line "sometimes solutions aren't so simple" is saying that the simple solution to depression is just take some medicine and don't feel sad anymore, but in reality, the illness isn't that simple to conquer. I get the idea that it wasn't this person's first attempt at suicide with "In cards and flowers on your window, your friends all plead with you to stay."

However, no matter what the meaning of the song is, it's beautiful.