I think this song is about waiting for someone never coming back. I think that she is waiting but it is never coming back. She wants the best for the person but wants to be apart of their lives. When she says " I know it's for the better" she is saying that she knows not being in that person's life is better but she still wants them. She just wants to show all the emotion she wants but can't because that person isn't there. When she says "I never grew up with you and you're not my waiting room" she is saying that she can no longer wait for that person anymore because it is only going to hurt her even more. she soon gets tired of waiting.
I think this song is about waiting for someone never coming back. I think that she is waiting but it is never coming back. She wants the best for the person but wants to be apart of their lives. When she says " I know it's for the better" she is saying that she knows not being in that person's life is better but she still wants them. She just wants to show all the emotion she wants but can't because that person isn't there. When she says "I never grew up with you and you're not my waiting room" she is saying that she can no longer wait for that person anymore because it is only going to hurt her even more. she soon gets tired of waiting.