You can't just tell an addict to seek help.. you have to go yourself to a FT and set an example.. after a few months you can have the FT invite them on a business card written by hand and name to your wife and leave the card with her...
You can't just tell her to seek help, drop that in her lap and walk away... No addict is going to act on that
Set an example, follow through, get a hand written invite for her, and otherwise live your own life and protect the family you can... She's an adult and she has to make some choices for herself... give her what she needs to GET the help then detach
FT will do you good, even if its to end a marriage or detach from a troublesome marriage... you don't need her to go, don't even ASK.. just go yourself and set an adult example