(pt2)I have talked with her about those things and she won’t budge. I really want her to listen and embrace a better way of thinking, because I can clearly see that this kind of thinking is not healthy for her, it’s plain wrong, and it might actually hurt her while she tries to look like a cool person in front of her friends, that are mostly male and older than her. How can I try to make her adopt a less harmful view of things?

It might just take time and experience, if she’s young.  Instead of responding every time she writes that stuff, I think ignoring it and posting your own feminist statements/weblinks on your facebook.  Proudly declare yourself a feminist on Facebook and add friends with like-minded beliefs.  Delete any messages from her attempting to argue on your posts.  Tell her these posts you make are not up for debate and that you’ll delete her if she doesn’t stop.  By inundating her with your own feminist beliefs and external articles that promote and prove a need for feminism, you may be able to change her mind over time.  This could take years, mind you. 

You don’t say how old she is, but it’s pretty common for teenage girls who are insecure about themselves and swamped with contradictory expectations about their own gender to try and gain validation and confidence by throwing other women under the bus.  That was true for me as a young teen, and I know a lot of women who acted the same way around that age. 

I think posting your own messages independent of her without engaging with her too much would give her a chance to read those things without pressure and slowly change her mind.  Especially if you post things that are inarguably important like stories about big rape cases, sexual assault statistics, street harassment movements, etc.  Stuff that would be hard for her to ignore or make up a counterargument for.  Also, block any mutual you have who often reinforce her sexism/racism and post the same kind of content, so at least you don’t have to deal with too much of that and she doesn’t have someone to always back up her shitty arguments if she brings the over to your page.  Followers, feel free to contribute your own suggesstions.