Ehhh, I highly doubt it. I have no idea why several people on here seem t have created threads about the same thing, but using different titles. My opinion hasn't changed... Isolating yourself when trying to get clean is and will never be a good idea, we are social creatures by nature... why in the world would you isolate yourself when you are going though one of the most difficult things to do alone ever?! It's even hard to do it with help, let alone completely isolated.
It may be possible, but I really, really, really recommend getting help. I was addicted to heroin for a few years, and found that the most difficult part of recovery came after I overcame physical addiction. My underlying problems (depression, grief) were still there, and louder, having been suppressed for so long. It took me a solid 2 years to get back on my feet, with ample help from therapy, depression medication, and community. Don't go through it alone if you can help it.
I read this story about an army veteran who had a cocaine addiction. When he decided to quit he locked himself away in a room for three weeks. He'd talk to nor let anyone into his room. From the time he came out until the day he died, he never touched cocaine again. That's proof that if someone is determined to overcome their addiction no matter what it takes, they can do it.
I think this question shows the difference between abstinence from drugs, and recovery from drug addiction. I believe it is possible for a person to stop using drugs, and sustain abstinence from drugs, alone. But that would be similar to what they call a "dry drunk" in AA. The person may have removed the drug from their life, but they are unable to recover from the psychological factors that made them an addict. I think that other people-- whether it be other recovering addicts, a counselor, or a psychiatrist-- are crucial to a full recovery.