I'm a recovering alcoholic and only in AA did I straighten out some underlying issues I'd had, like growing up in a mad alcoholic home. It's possible, but I'm not sure, that starting to lose the fear I'd always had (the corrosive thread running through my life) had a knock on effect on stopping my stuttering. The key was to get honest, I didn't know what real honesty meant and I'm still learning but I became willing and open to it.