My ‘husband’ was the same.
‘Husband’ only sniffed when he was with family that partake or with his friends that he too said are like family. But they are only ‘coke friends/family’ not normal, real friends. My husband had a real life before he was introduced to these people. You sound so much like him, like he couldn’t not be with these people. You have to separate yourself from these friends if you want to stop. You can still have a social life without them as you said you can drink when you are abroad on holiday. It is a difficult choice, your health or your life with your friends. I’ve seen it, I have been there.
I wish you well.