Brief Answer:
This is a pretty standard issue.

Detailed Answer:
The first and fundamental problem is that he doesn't really want to quit. He doesn't see much of a downside. To me or you 300,000 is a downside but this isn't true of most people who can spend it like that.

Ok, two possibilities: he's had negative consequences from it or more likely, he has not. If he's been broke, in the ER, with nasal lesions that aren't healing, then you'd say ok, I love you, here's the tradeoff, and how worth it is this to you?

But what if he hasn't had many problems? XXXXXXX CK, Dice Clay, Seinfeld, XXXXXXX XXXXXXX ..

Ok, I could say look at the age distribution of cocaine users and realize that it is literally a dead end. The body cannot tolerate cocaine at a certain point and it becomes guaranteed to cause serious harm/fatality and you can tell because there aren't any old cocaine users. This age distribution issue can be illustrated by comedy people. There isn't a medical reason, but you don't see many even middle-aged comedy people, cocaine users, or in the case of XXXXXXX Wiliams, XXXXXXX XXXXXXX and many others that died, comedy people who use cocaine. You don't get to be old if you use cocaine.

Next part. Suppose he says he agrees but just cannot quit.
There's fighting it. It doesn't work. It makes it feel even better using it.
Avoiding it by getting your money harder to access or moving away from the previous sources of cocaine.

Re-labelling is hard on this one and easier on food issues or even with alcohol or narcotics. You can relabel the withdrawal feelings as a positive feeling of being better. You can relabel substitutes. But this isn't quite as likely to work with cocaine.

Transcending: this is putting something else into the same picture to change it. Inviting one's cocaine suppliers to an NA or AA meeting or into therapy together is one such approach.

Let me know if I can assist you further.

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Brief Answer:
it is an individual situation

Detailed Answer:
AA and NA do actually work but work best if someone lets it into their life. So, if someone is denying they have a problem it might work or not.
Intensive inpatient or outpatient therapy is best when someone has to get out of their current environment. If someone is in need of being in a shelter and drugs are involved, this is a good fit.
The end goal is to have an entire social situaiton that supports NOT being on drugs. So, both NA and AA and residential treatment miss the point since someone's general life isn't directly affected by any of them even as much as you having a nice lunch with them.
If someone is making 100's of thousands a year, they have a life and going into residential treatment isn't changing it. If they are homeless and the residential treatment works on social situation, it probably WILL especially if they change neighborhoods. AA and NA on the other hand are more likely to work with someone who has resources.

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