Congrats on the 13 months!
I am at 14 months now and I too have this struggle, in a way I think it is kind of natural. I just got to keep the faith and know I can not pick up. I have been kind of avoiding the social scene for just that reason. Last time I went out was with a divorce-seperation meet-up group of people I never met. Of course they met at a bar and then went to another bar. Most people there were meeting each other for the first time so there was minimal awarkwardness. I just kept myself busy talking. I always had a coke in my hand while at it. It just gave me comfort having something. When it got to be too much I just said good-night. When I left I talked to my sponsor on the way home. I made it, I survived and I was pretty dang proud of myself for doing it and making it. You will do great :-)