Heyy. Natasha doesn't seem like a really good friend especially if she's abusing you. Not only is this seen as harassment (to an extent,) but it's also illegal. If she was your true friend, she wouldn't even think about causing you physical harm. Things like that disappoint me in people, and for them to just sit there and feel like they can hurt you is wrong.
If you haven't already, you need to bring up the fact that she's been abusing you and you don't appreciate it. Nicely ask her to stop, and see where it goes from there. If it continues to happen, you need to tell her to stop again, but perhaps in a forceful manner. After that, the only real thing that you can do is to ditch her as a friend. It's not worth it in the end, and honestly she isn't a good friend if she's going to hurt you constantly.
I'd like to note that sometimes we do have something mentally wrong with us (not calling her crazy, but as you think she's insane, I thought this was appropriate.) We can't always control the actions which we do, and for that we need attention taken to us. Perhaps going to therapy with her could be an ideal choice. I know she won't want to, but you need to eventually help her improve her actions if you do think that there is something wrong. This would show that you're a true friend through everything. :/
Other than that, you have to draw the line somewhere. I wish you luck.
~Wayne
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₪This mix could burn a hole in anyone.₪