((((justsad))))
You can't help them. They have to want to and then help themselves. And you MUST help yourself. Allow yourself to feel the pain of the abuse and betrayal and let it motivate you to get out and away from that hell.
I absolutely would call the police on a loved one if I knew they were drinking and driving. Ask yourself this... would you be able live with YOURSELF if you let this go on and they killed someone? If you don't call the police, you are betraying YOURSELF and every other law abiding citizen on the streets.
Bless you, I know how you feel. We have to help ourselves. Friends and family are often so manipulated that they forget who they are and that they are alive and deserve love.