#1 beating your self up over this will accomplish nothing!!!!
Sit down and honestly evaluate what you were doing right to stay sober and then add to it.
Next figure out what led to that drink, what were you doing or not doing?
Ask your self honestly "Am I doing everything in my power to not drink again?"
Is there anything anyone has suggested you do that you have not done yet? If there is then ask your self why?
Is the answer that you are not ready to do what ever it takes to get and stay sober?
Staying sober takes action, not inaction, it takes mare change then simply not drinking.
I spent a lot of years continuously relapsing because I was not willing to do what ever it took to stay sober, I wanted to stay sober my way, not the way that worked for someone else.