I think the song could have two views. One would be when you're alive, you should appreciate the people who love you because you won't be with them forever. If there is a heaven we all go to, then I think the song could be saying that you shouldn't be afraid to die because you'll find a greater life on the other side. But the way the song sounds doesn't really fit this meaning, for me. It gives me the sense that you've moved on from a life you loved, but didn't want to leave because you were comfortable with it. And now that you're moving on, you realize how good life is.
I think the song could have two views. One would be when you're alive, you should appreciate the people who love you because you won't be with them forever. If there is a heaven we all go to, then I think the song could be saying that you shouldn't be afraid to die because you'll find a greater life on the other side. But the way the song sounds doesn't really fit this meaning, for me. It gives me the sense that you've moved on from a life you loved, but didn't want to leave because you were comfortable with it. And now that you're moving on, you realize how good life is.