<human>: Pretty much that. My friend came from not-so-good background and got pretty into the drug scene in high school (selling/doing). Came to college and cleaned up his act for about a year or so. Ended up dropping out of school, and is now living on his own off of money he acquired through a trust fund kind of thing.

So basically, it's really hard to see my friend (let's call him Rob) without him getting wasted and staying up all night doing coke. It has gotten to the point where he is starting to act like a textbook cokehead-very aggressive, very "supreme" feelings- and has basically just been acting like a dick to everyone. I've tried to talk to him a thousand times about it and he swears he has it under control, etc. I'm not anti-drug in the least, but I've been around enough addicts to know what one looks like. I'm at my wits end. He's starting to make me hate him with his behaviour and his inability to talk about anything that isn't drugs or howwww fucked up he got, etc. I want to be there for him but he's driving me and everyone close to him away. I'm afraid he's going to put all his money up his nose and then be legitimately fucked. 

I'm aware that this problem may be entirely too big for me to handle, and I'm not even sure if this is the right sub for this but I really need some help. I've tried the sit down and talk method, I've tried the angry yelling method, I've tried the texts and the phone calls.

I don't want to find out my best friend died or totally fucked up his life because of something as stupid as a bag of white powder. Please help.

Can you succinctly summarize the text in 1-3 sentences?
<bot>: Best friend has a drug problem, I don't know what to do. He has no close family, only his group of friends that I am a part of.