Freddo: Just shut the door on her and don't take her phone calls. Forever.
Use this stupid sister and her stalking of you to your advantage. Ignore every attempt by any elder to engage you in conversation. Firmly tell them to leave you alone.
I have to agree. You are at such a terrible point in time with the locals. Just shut them out of your life and advance your fade with leaps and bounds- that's what I would say.
I know it's hard to do. But let everyone think what they think.
Screen all your calls. You can tell anyone that wants to visit your home that they must call from their cell phone as you won't answer the door. If any JW's try to stop you getting out of your car or at the market, just be strong and say "I am not discussing it." If you need to say more, add "...As long as that sister is free to harass me and you elders don't call her off, I cannot talk to you either."
The main thing about a fade is family. You lose "friends" and have to adopt an attitude of "don't give a crap" about some crazy pioneer sister or the elders. Just don't do anything openly to cause them to take judicial actions. Meanwhile, talk about normal non-JW things to family to the best of your ability. Let them misunderstand and don't even try to explain anything about your fade to them. "Let's not talk about that. Let's talk about good things, family matters." That should be enough.