It's actually not based on a true story. The plot and characters are crafted to tell a unique fictional tale that engages the readers' emotions and imagination.
Hard to say. You'd have to look into the background and the author's statements to determine if it's truly based on reality. Maybe it's a blend of fact and fiction.
One possible theme is perseverance. Since it's based on a true story, it likely shows how someone overcame difficulties by just keeping at it, with breathing as a symbol of their continuous effort.