The movie was made in the 90's or early 2000's. It was set in modern times. I probably saw it on Cinemax, HBO, or Showtime.
I don't remember any major stars being in it, but one of the lead actresses may have had long brown or black hair.
It was about a young man who became acquainted with a mother and her virgin daughter, who seemed to be in her early 20's. The pair may have lived on an island or in a very remote region where they were far removed from neighbors. The daughter was very sheltered and inexperienced, but not stupid. Eventually, the young man lured her away (he may have discovered something sinister about the mother) and took her to a motel, where she lost her virginity to him. The irate, crazy mother tracked them down.
I forget how it ends, but I think it ends badly for the mother.