Welcome to SR and sobriety. Good choice.
What sort of therapy are you starting? Therapy itself can be very useful in recovery.
How are you planning on managing the underlying depression when you can no longer self-medicate? A psychiatrist with a specialization in substance abuse treatment as well as mood disorders saved my life, and could be an extremely valuable resource for anyone.
Cold turkey can be painful to dangerous, it's not a bad idea to consult with a doctor about your physical cessation. The symptoms are largely dependent on drinking amount and duration, but everyone is different, and this is only a guide. A doctor can also help with medications to ease the transition and advise you if they feel that this is useful or necessary.
Books, audiobooks, and web sites are fine, but a more structured plan is best.
I'm a terminal agnostic and AA didn't work for me either...but there are some atheists/agnostics that makes 12 Step work for them, so I wouldn't discount it entirely.
There are a ton of secular recovery programs like SMART, AVRT and Lifering as well, there's a whole forum devoted to them. AA isn't the only game in town.