How do I end a childhood friendship as a senior in highschool?

Hello, I(18F) and my childhood friend(17F), lets call her M, have been friends since 7th grade and I think it's time to end our friendship

For some background information; M and I are very different; our views on things are very different but our morals have always stayed the same. To put it frankly, she's boy crazy, M will get with these horrible people who treat her like garbage (ex: manipulative, narcissistic, only want her because shes pretty, type of stuff) it's been this ongoing things forever and whenever I say anything about it, its "you've never had a relationship, you don't know what you're talking about" and that really stings, and she knows it does because i've opened up to her about it.

However, I fear these past couple weeks have been the final straw. M is currently talking to two boys and honestly it's none of my business who she talks to, i just want her to be safe and happy, but it turns into my feelings being hurt when she asks for my advice and gets mad when I give it to her. She is talking to this one dude who specifically said he "ONLY WANTS M TO SEE HER NAKED" and they still went out on a date and texted me that she likes him and that he explained that they talked about it. She asked for my advice and i told her that him apologizing was the bare minimum; and she responded saying "to you." so I didn't respond.

A couple days pass and dude number 2, her, and me share a class together. I had a terrible weekend so I asked if I could sit and talk to her. She proceeds to sit with that dude and flirt it up all period. I was going to talk to her about it but before I could, we had our lunch. We were talking and i accidentally said something wrong and she asked me condescendingly if i was stupid.

Stuff like this has been happening for the past couple of months and I can't take it anymore. I have had talk with her and she tells me that "she can do whatever she wants and i can't control what she does" and she right, I do not. But that doesn't mean I want to be around decisions i don't agree with, I have way too much to worry about, going into college and getting everything settled. My mom tells me it's because i am very mature for my age so most kids my age won't understand theres more to life than boys and things like that will happen in life everyday.

I really wish to end this friendship, I feel like it's draining and does nothing but bring me stress. I also don't even know if it's worth it, It's my last year and I don't want any unnecessary drama, but i'm not sure I can keep this up.