So when I was in 6 grade I watched the fallowing movie on late night HBO. This would have been around 2001-2002 and the movie couldn't have been older than the early 90's.
It ran something along the line of a mother and daughter on and Island (or either they lived close to a shore in the neck of the woods) and this man (a young man) rides his motorcycle around and falls in love with the Daughter. The mother is upset with this and tries to ward of the young man. The daughter ends up running off with the young man and has sex with him in a motel, where when he looks up during the act he see's the mother stabbing him (she obviously doesn't its more like a trick of the eye/him imagining it). The film goes on, and it turns out that the mother wanted to keep the daughter on the island so that the daughter would kill the mother (which there mother's mother had her do the same thing)and carry on the tradition. I believe there is something along the lines on an abandoned mineshaft where the murder had happened of the mother's mother--infact there is a creepy little scene where the mother is pointing a gun at her mother and the mother runs up and puts the gun in her mouth.
The movie might have contained the words "beautiful" "Heavenly" or "Creatures" in it. I have watched the movies "Heavenly creatures" and "Beautiful Creatures" and these are not the movies.
Help help help help please!