I have been trying to find information about the hope for recovery for previous meth users, but there doesn't seem to be a consensus. Some sources say that meth causes permanent damage to the brain, while others are a little more hopeful and say some important brain functions might recover.

I used meth about fifteen times, which I gather isn't a lot in comparison to other meth users but is still a considerable amount. For a while I have felt paranoid and anxious and it has been more difficult to perform daily tasks and just generally think straight. Also, things I used to enjoy are not really that enjoyable anymore.

My question is, will I be able to have my brain back? If so, how much of it? Will I ever go back to being my old self?

My dad requires me to take weekly drug tests since he found out that I was smoking marijuana. My first test came back positive for marijuana and cocaine. I was not surprised about the marijuana because I had only been clean for five weeks, but I have never done cocaine. Is there anything that could have triggered a positive result? Could opium or mushrooms or any other drug possibly trigger this positive result?

1) I found a white powder in my friend's car and I think it might be cocaine. I'm not sure if it is or not. I don't know if I should confront him with it or what I should do. I don't want to see my friend get hurt, but if I'm wrong, I don't want to falsely accuse him of something like this. How should I go about handling the situation?

2) I am a first-year business student and have a little sister who is a junior. I think she is doing cocaine because I found some "paraphernalia" in her room last week. What can I do without damaging my relationship with her?