Your sister loves you! When I was going through something similar I felt ashamed when my family knew what was happening. Were you afraid of what she'd think of what you did? I was surprised by the reactions from family members that I expected the worst from. One family member even told me they had done the same thing a long time ago. They understood, and it made me feel better. Not all of my family was so understanding, but they still loved me, in their own muddled ways.
I'm sure that no matter what, your sister isn't going to give up trying to help you, number one, so maybe you should just get used to it and accept that she cares about you. Number two, she should still respect your privacy! If she becomes really hard to take, maybe have one of your helpers talk to her about backing off?
It sounds like she's just trying to be a good big sister. It would hurt me a lot knowing that my little brother was going through that, and not being able to help.
Sometimes letting an eager helper know what EXACTLY what they can do to help you, (giving them specific tasks,) and then letting them know you appreciate it, will calm them down. Think of something your sister could do for you from where she is that wouldn't be interfering with your life.