Hmmm I didn't want to alarm you with this before OP, but don't place too much faith in "the professionals" to sort him out. I had a partner (another one, I didn't half pick 'em back in the day!) who went into full-on drug psychosis. I assumed the appropriate authorities would step in and see to it that he got proper treatment, but no one really seemed to give a shit. I expect they have enough on their plate without these groggy weirdos who aren't easy to diagnose, partly as they might have nothing wrong with them that's not of their own doing.
It's just so hard with these losers to know how to separate fact from fiction. They hardly know themselves, as they spend so long in a delusional drug state that reality must seem like a vague dream. With my ex-DP, I ended up having no idea who he really was. I was tortured by memories of the happy times we'd spent, but there was such a broad and extreme spectrum of behaviours that I just gave up trying to work out which one was "really him" - if indeed any of them were.
I am sorry to keep using harsh terms to refer to him, but in my experience being an addict does not mean being an arsehole, as your friend proved. It seems to me with blokes like this that they are primarily an arsehole and we just excuse them on the grounds of all the shit choices they then go on to make, which make their lives so much worse.
I also wonder if they kind of get addicted to being rescued, a bit like that Munchausen's by proxy thing where mothers harm their children in order to receive attention from healthcare services.
Just warning you that although you may long for the "professionals" to "fix" him, it is likely that he will just drift around making a mess of his life for ever. That is the sad story, I'm afraid. You need to accept it in order to let go. It is not your job to secure proper treatment for him, because it's quite likely that there is none, and/or no one is going to pay him that much attention. My ex attempted to kill someone, and even that didn't get him into proper care.
Sorry OP, I know how hard this is. I cried a river over him, and others! It felt absolutely devastating at the time! Now, I just wonder how I tolerated their shit for more than 5 minutes.