I probably should have asked this before I made the edit.
If someone writes/records a song about a person (in this specific instance, they even included their name in the title), is it dedicated to?
I have also seen ‘tribute to’. I know there is a ‘based on’, but that is different.
“Dedicated to” is often more specific - as in, “this song is for Dora Hand, in memoriam”. Checking the lyrics, I wouldn’t be surprised if that was the sentiment here, so I expect it’s not wrong per se, although I probably wouldn’t have added that myself.
As someone who has written many songs about past relationships, I would vote for using the Dedicated To relationship. I have used it many times and I know that it’s 100% appropriate to the way I wrote my songs. If one writes a song about someone else, it is dedicated to the memory of, or relating to or about the person involved. A tribute could also apply but that has a different connotation. I think Dedicated To is most certainly the best way to use it.