Definitely not. 'Whiskey Lullaby' is purely a work of fiction. It was crafted to touch people's hearts through its lyrical tale, not because it reflects actual happenings.
Another theme is loyalty. His loyalty to his agency or to certain characters is often explored in fanfics. For example, there might be a story where he has to choose between his loyalty to his superiors and his personal beliefs. And this creates a lot of internal conflict and makes for an interesting read. It can also show how his character develops when faced with such dilemmas.