Damn. Friends atrophying and that feeling of waste - not moving on - total inertia. All of that resonates with me as does the fact that the drinking wasn't every day but when it did happen it was to obliteration. What age are you David? I'm 41 now - I hit the wall at 38 but it has only taken me until now to start making headway - well the last year anyway. I wish I hadn't wasted those 2.5 years and I also wish I hadn't wasted the previous 10/15. Having said that, I do feel like I'm on the right track and that fear of what lay ahead in the sober world has now gone - doesn't mean my life is perfect. But that feeling of being overwhelmed does go away with repeated commitment to getting sober. I also found that the depression and anxiety - for the most part it was caused by alcohol and it wasn't just something already there that I was using alcohol to address.
I hope you can climb out of the hole and start getting used to some prolonged stretches of sobriety - start slowly getting used to it until eventually you are out the other side and not wanting to go back into the madness.