I know what you mean when you say this makes him sound even worse than he is. And I bet he is goofy and fun with you! I dont really know what to say...but you should really just tell him "listen, I love you to death, but i cannot handle when you do that! It scares me and it makes me really upset. Drugs are not the answer to life, can you please try to work something out with me here where we both feel confertable?" You should try something along those lines...good luck!