lovinghalacha: If your parents have good judgment, and won’t overreact, (or if they won’t do anything without consulting their Rav,) you should speak to them first.
If you really feel you can’t trust them, then you should speak speak directly to a Rav or Rebbetzin you trust. If you need to, you can press *67 before you dial so they won’t know who you are.
The relative should only be spoken to after that.
Hatzlocha!