What she was facing is honestly what I see a lot of writers facing. In an effort to amp up the sensuality of the story, authors just start inserting sex scenes every time they turn around. In the end, plot is lost in the story and the author feels frustrated because the story is going no where. Don't panic! This is something that many authors face with their stories.
I want to keep this short and simple today. There is an easy solution to this and yes, it involves plotting and planning. In essence, as you look at your story, you need to "pencil in an appointment for your characters to have sex." By doing so, you can build plot elements to get them all hot and bothered and ready to explode into that scene.