Feeling pretty gutted

[robvalue]

I'm really sorry to hear things have gotten so bad I think you're a lovely person, and very reasonable, so whatever issues your sister has with you are very likely to be her own problems in my opinion.

The only advice I can give is how I have handled very similar situations with family: emotionally detach yourself from them. I know that's much easier said than done, but it's the only way I have been able to survive the bizarre relationships within my family. Over time, I stopped caring about what they say or think about me. Giving them "one more chance" and trying to meet them in the middle was just setting me up for failure one more time.

Again, I'm really sorry, and I hope you find a way to cope. Changing your sister is probably impossible, so all you can do is alter the way you react to her.