A sister to sister relationship is hard when one isn't being a good sister. You have done what you can - sorry she isn't acting kindly toward you.

My guess is she isn't going to do anything differently. She sent a copy of what "her plan to repay you" is, her will. My thinking is this resolves her of her responsibilities toward what she owes you. But in truth, it is unrealistic of her to think that way. What a jerk. It is sad.

Does she see you need that money? Does she care that you want it back?
Is there a reason she thinks you don't deserve it now or in the past? I don't get it. Darn, money can be the cause of so many rough relationships.

Small claims court is one idea, I'm not smart when it comes to what other actions can be taken, but if you truely need the money and can stand the stress of getting back what is rightfully yours, go for it. It is already apparent that you are the one who wants the sister relationship, and her, not so much. Sorry if that stings, If it were up to me I'd give you a new sister. .

It hurts more when you aren't the one who did the rejecting I think. Sounds like she just doesn't get it. And at this point, probably never will.

God bless you sweetie. Good luck making your decision. I'ts so hard I feel your pain