I'm glad to hear you are already thinking of this and have already decided it is best not to go.
I know it is a tough, emotional decision. The part that wants to be there with your friends celebrating this important occasion is strong. But I just want to tell you that it can be done and it will be ok.
Mid April 2016 I got out of rehab. In May of 2016 two of the most important people in my life got married, 2 days apart. My brother and my best friend. I was to be my brother's witness and I was the ONLY friend invited to my best friend's wedding. They had a small ceremony with only immediate family. Obviously before rehab I had been planning on going. Once I got out I really evaluated the situation and knew that it was just too risky for me- the international flight all on my own; two major, emotional events in a short time span; so new in recovery. I didn't go. Everyone understood. My brother is still my brother. He and his new husband even did a special photoshoot with the photographer, holding up pictures of me throughout the day. My best friend is still my best friend. They had a lovely, small ceremony, just what they wanted. I got to FaceTime with her while she was at the salon getting ready, later in the evening we spoke briefly and I spoke to her husband to say congratulations.
They were both understanding, I didn't ruin my sobriety, and I didn't ruin their special days by being there either a. uncomfortable and nervous or b. drunk and out of control.
Life does indeed go on without us!