RE: I have been Disowned by My Sister
As you grow older, when all the petty vanities of youth become less important, you will see that the world is not as nice and friendly a place as it seems now. That is when you will learn just how important family is.
Think of it this way, nobody says you and your sister always have to like each other or agree on everything - but you do have to love each other. (actually, that is a rule which should also be used by married couples who want their marriage to last).
Someday you may have kids...let us say a little boy and girl. Do you know what will be one of your most important wishes for them? That they continue to love and support each other for all their lives.
I practice what I preach and I can tell you, even at my age, the love of my family remains strong (or should I say, stronger than ever) and provides me with most of the happiness I get to feel.
So, do not wait too long. Find a way to open her heart to you again.