I am sorry you are worried about your daughter.
Does your daughter think she has a problem? You can offer support to her, but she will need to decide to seek help for herself. For you and your wife, you might check out AlAnon and take a look around our boards. You will find lots of information about alcoholism and lots of support.
Our deepest fear is not that we are inadequate. Our deepest fear is that we are powerful beyond measure. It is our light, not our darkness that most frightens us.