Oh no, I didn't do anything. I was the DD for him and his friends. I could not touch anything like that because my anxiety is so high. But this was a one time thing for him he normally doesn't do anything like that.
You asked for advice, so here you go: STOP DOING DRUGS. Major, minor, whatever. It's a stupid thing for anyone to do, but for someone who is prone to anxiety it's the dumbest thing in the world. And your fiancee needs to do the same. You two are getting married, and will perhaps one day become parents. That's a good reason to stop and get clean. Make it your New Year's resolution and stick to it. Celebrate birthdays by going out for dinner. It will probably be cheaper too. No more drugs, ever again, and it starts now.