Hi Verity,
I know the feeling. Believe me, there always seem to be people that drank more/used more etc. but trust me there are many people just like you, that drank infrequently but when they did, look out! Either way we all share a common goal and desire to be free from drinking/using. To be sober, to be clear, to take back control of our lives from the bottle (even if it was only once a month).
Keep going to meetings and keep trying different meetings until you find one that "clicks" with you, it may take a few meetings or more but just keep going.
All the best to you on your journey!