Over or Not

If its over, then it should be done, 
And if it isn't, then its not 
But I'll tell you, I've not even begun, 
Gimme' a chance, I'll show you what I've got. 
This is goodbye, at least for now, 
Unless you'll give me another chance. 
If you want me gone, I'll disavow, 
But I'll be back if you ever want 
That one last dance