If you are an alcoholic, you probably should check out AA in addition to checking in to a detox/rehab program where you will have a therapist and a psychiatrist. As a matter of fact, many "real trained and certified therapists" will suggest that you at least check out a few meetings.
What's important is to know that if it doesn't work out, it doesn't mean you've failed. But it's really, really hard to stop drinking when you are an alcoholic, and it would be foolish to exclude any safe solution that could potentially help you recover from a fatal condition.
When getting sober, there are worst things you could be doing with your time than socializing with other recovering alcoholics for an hour or two, even if you don't like the message.
I should add, I am an atheist and it was never an issue in all my time in AA.