This just sounds like something from Jim Carroll's book The Basketball Diaries. Not gonna 'splain it so just Google it. Anyone doing what your h is doing is obviously not doing anything "normal" in my estimation. Smoking pills?! Come on.....
I'm an alkie, not an addict. Still, I just spent a little time searching for answers to what you're asking. It seems most likely that he's smoking meth. Why on aluminum foil I don't know. Perhaps because it's easier to get rid of than it is to hide a pipe. I don't know.
Maybe repost this under the Substance Abuse forum.