Hey clueless, the reason we tell you to keep your distance is we know what devastation living with an active drinker can bring to your life, and to the life of your family.
I am on day 18 of sobriety, so this is all still very fresh in my mind. If you read our posts here about our lives as drunks, the common thread that you will find is that we all had one mission in life which was to drink., and we weren't going to do any thing that would jeopardize that.
What started out many years ago as a simple way to deal with stress for me ended up with me being physiologically and emotionally addicted to booze. I lied to my wife, I spent great sums of money buying booze, I was always finding ways to get out of the house to drink, and I was totally unpredictable at times. All the events that I went to where I assumed that no one could tell that I was drunk, are embarrassing as hell to me today, but at the time, in the fog of booze, hangovers, and scheming for more, I just didn't notice.
I tell you all of this to say, that bringing an active alcoholic into your life can have far reaching consequences to you and your family. You have to keep your guard up because when your sister is drunk, she is a different person who would most likely not stop for anything to get a drink.
Until she finds her bottom, or until she wakes up one day and says no more, I would keep my distance. You don't need that in your life, IMHO.
Finally, it would also be good for you to hear some advice from some of the old timers, though I do have a feeling that they may feel the same way. Don't worry, they will be posting after me, that's what makes this community great!