Forgive me for asking, but did you go by a different screen name before??
I'm so sorry the things your sister said has upset you. I have a sister, and I know it would break my heart if she was upset with me.
That being said, you have to keep your side of the street clean and apologize. Whether you think you were wrong or not. Unfortunately, when we are the ones who offend through our drinking, we are the ones who need to eat crow, at least for a while.
I hope you can patch this up. Sisters are forever.