Well... let's not say it's "ended" Sally. Never say never! Let's say it is a relationship in hibernation at the moment.
Frankly, I have no idea why she doesn't talk to me. She has periodically come out of this information blackout for a few weeks, but she always disappears again. When she comes "out" I don't want to press her too much, but I try to find out what I can about what is wrong... she has said a couple of times now, "It's not you, it's me. I'm just a bitch." Maybe she is struggling with some horrible self-esteem issues she feels I wouldn't understand. It makes me sad, because I feel like she doesn't even know me, we've been estranged for so long (most of the past 8 years I would say).
I have done some shamanic work around this issue, and received some pretty startling insights that feel "right" to me, and have given me some peace regarding the issue of her ongoing separation from me. But until we really heal our relationship and talk as adults in the present time, I can't really know if any of those answers jibe with my sister's experienced reality.
I really believe this relationship will eventually shift and heal (unless something happens to one of us... which would be VERY sad, wouldn't it?) I love my sister so much, and I feel that deep down she loves me too. Hopefully she will come around while we are still young enough to enjoy some time together, knowing each other as the adults we have become.