Good-Bye …

After saying goodbye to my daughter, I was back into my car. A song started to play, and sang "I am a visitor here… I am not permanent.". I started to think about the word "Goodbye".
When we say Goodbye, we believe we will see each other again in the back of our minds, with all the hopes and the visions of the happiness of being reunited in the future. When we know we are not going to see each other again, we say "I love you", and then we say "It is okay to let go", and then we are repeating "I love you" over and over again, until the person can no longer hear, but we never say "Goodbye", because there is NO "GOOD" anymore.
But what if, the moment we said "Goodbye" was the last moment … This thought makes me very sad …