Time to Rebuild

[Jen_Jam]

OK, need the DB line of advice here.
In our teens/20's, H and I used to be into drugs. The heaviest I got to was speed, he to coke. We would NEVER go to heroin.
Like most things you do when you're young it's now gone, occasional smoke but nothing more.
H has a friend who takes ecstacy and cocaine when he goes out (as does his girlfriend) and this friend has been asking H to go clubbing with them (I'm not invited cos they know I won't enjoy it - I have no problem with that.)
Now, I have no problem with H going with them, and I'm not bothered what drugs they take. But I don't want H to take either of these.
We talked about it last night. He told me that he certainly wouldn't plan to but if the mood took him he might. I stated very clearly (without shouting or name calling) that I cannot accept that and that basically he can choose - me or the drugs. I told him as well that he could do it behind my back but the chances are I'd find out anyway (I know what someone who's been on these drugs is like, I mean I can recognise the comedown).
So he has chosen me. I did go on a bit - it was something I meant to bring up a few weeks ago but didn't as he wasn't off out with his friend, but he was considering going tonight (he isn't though - he's got a bit of a cold).
So - I suppose I'm looking for a "how did I do?" Stating boundaries? Or making demands? I did stress as well that I had no problem with him going clubbing/anywhere else with this friend, the only sticking point is the drugs.
What do yous think?