You know, there's no a perfect friend. Everyone has flaws, and you too. We have temptations and mistakes. The best solution for that is confront her. Say to her that her actions are too annoying, but say it in a nice way. Ask her if she has a problem. In that way, you'll understand why her attitude is not good. Advice her to change and say you'll never leave her in times of ups and downs.
Don't let that thing be a cause for your separation with your friend.
Well. I'm in 8th grade and I have a friend, Alex. She wouldn't be my friend if it were up to me.. It's just nobody likes her. Nobody ever has. She's always mean and temperamental all the time. She has a hitting problem. I'll say that much. She gets agitated easily, She's a control freak too. If she doesn't get what she wants she goes and takes her anger out on someone or something and then 5 minutes later she's perfectly fine and over it. When I came to this school, I had a lot going on, you know.. In my personal, family life and such. I had just gotten over a self-harm issue. But she's been really abusive, as I've touched base on. I mean, referring back to the hitting problem she has, she's really abusive. Like, a little joke, she'll hit me. In P.E, she'll sneak up behind me and hit me for absolutely no reason. What I would do, is just confront her about how she's acting towards you, and tell her that she maybe isn't the same as she used to be, or she's getting a little too mean, and you think it's putting a risk up to your friendship... Just do it nicely, you don't want her to get mad. I haven't actually thought of a way to pivot out of my never ending days of getting practically beaten up by my "friend." But yeah.. Just confront her nicely, and tell her how you feel. Hope this helps a bit.
And In The End, We'll Fall Apart. Just As The Leaves, Changing Colors. And Then I Will Be With You.