I think you might have it wrong about the depression, FF. It's NOT your fault. That's what depression does. It sucks the life out of life and the whole point of it is to make you not want to do anything. Sure, lifestyle changes certainly help, but I think you need more than that - from what you wrote it sounds like you are severely clinically depressed. I would urge you to go to your therapist or psychiatrist and really be honest with them about how you're feeling; if they don't help you then you need to find new doctors.
You don't have to feel like this anymore, FF. You can deal with the depression/other mental health issues and really start gaining the benefits of sobriety.