My AB had issues with going to NA because he doesnt really believe in God either. He explained this to one of his therapists and they told him that God could stand for anything. The example they gave to him was this....
Group
Of
Drunks
Basically God can be whatever you want it to be. Like someone had posted before me, just a "higher power."
I also have always done treatment one-on-one and am a bit apprehensive about group treatment. But if you arent comfortable you dont have to speak and maybe it will just be helpful to hear other peoples stories. Thats how Im going to approach it and if the day comes where I want to speak then I will.