Good for you HGG, you are 100% right that you should deal with your issues before you get married, whatever approach you decide to take. That is a very mature approach, and you should be proud of that.
I think that ultimately, the fall-out from not doing the required therapy, if it includes a 12 step program, will be worse than the fall-out from potentially meeting people you know.
Hatzlacha, I hope you get the right advice on how to handle this.