These stories won't keep you from crossing the line. But they may help you see it a lot clearer.
And maybe even avoid it.

My Brother-in-Law is one of the best people I know, he is kind and loving and would do anything for someone if they needed him to no matter what. He has a substance problem and what he says is an addictive personality. My brother-in-law has a drinking problem, a meth problem, and a marijuana problem. In a repeat cycle he will drink, then use drugs to stop drinking: turning this awesome person into the scariest person ever. Everytime he drinks he blacks out, he can not control it even though he thinks he can. He hurts the people he loves hits them, screams at them, and has tried to kill himself multiple times. Then to quit drinking he starts doing meth, and becomes a hermit, and he is a very out going person, and funny. Then to stop the meth he smokes pot. This has been his pattern of life for the 6 yrs. that I have know him now. I believe that one of these things is what is going to kill him. So each day that I spend with him, I savor it as if it were the last. He doesn't believe he needs help, and in the end I believe help is what would save him.