I think that this song is about being in love with someone who you see on a regular basis that you have a good friendship with. Then, you realize that your feelings go deeper than the other person's feeling go, but cannot determine whether it is wise to let out your secret and reveal the feelings for fear of "losing what you don't have now." Maybe you have hinted at the feelings, but the other person doesn't seem to feel the same way. You are so in love with the person that it is not even a choice anymore of whether to love them. You just do. You would choose the anguish of keeping the friendship (and hoping for something more) because you at least get to see the person and have that type of relationship.
I think that this song is about being in love with someone who you see on a regular basis that you have a good friendship with. Then, you realize that your feelings go deeper than the other person's feeling go, but cannot determine whether it is wise to let out your secret and reveal the feelings for fear of "losing what you don't have now." Maybe you have hinted at the feelings, but the other person doesn't seem to feel the same way. You are so in love with the person that it is not even a choice anymore of whether to love them. You just do. You would choose the anguish of keeping the friendship (and hoping for something more) because you at least get to see the person and have that type of relationship.