If GHOST were a novel, and Demi Moore fell in love with someone after Patrick Dwayne died, and there was a strong romantic element between two living people what would the genre be classified as.
Would the ghost play a role in the story? The presence of a ghost makes it a paranormal, unless this is like Stacia Kane's Downside series, where ghosts are part of the worldbuilding. Then it would be fantasy.
Who does the story focus on? The ghost, or the woman's new relationship?
IMO, you're right that "paranormal romance" generally means a relationship that involves someone paranormal. Otherwise it's like a vampire romance where the heroine's husband is turned into a vampire, so she moves on and falls in love with another guy, while the vampire ex-husband tries to get on with his afterlife. I'm willing to bet this isn't what most readers of vampire romance are expecting when they pick up a book labelled "vampire romance".
Right now I'm querying a paranormal romance that has a ghost coming back to life and falling in love.