Definitely. I think if you're here, asking the questions, it's not too late for you. There are people out there who cannot or will not ever get better though and that's just how it is. I'm moving this over to the recovery forums.
I think there's a point someone will definitely end up in diapers. Or certainly some kind of psychosis, you know those people you see yelling at the trees, or fighting the air.
I know a couple meth addicts that are crazy right now...no one knows how detox will go for them because they are never not using.