I guess it depends on him.. If you say don’t come back till he is sorted. There is a good chance he will think.. Fuk it.. And just keep using and using. But that’s just a guess.
Ask him about his come downs, does he feel depressed or suicidal some times. Everyone who has coke has a come down. And they do get worse. Then psychosis can kick in. Try and tell him to play the tape forward.. Which means if he’s thinking of using try and imagine what the next few days will be like, is it really worth it??
Get him listen to some addiction recovery stories on you tube or podcast. They help me a lot.
Do you have children?