no just no. You're right about the part where a real friend would stick up for her, but I think you're confused. That statement does not and will never apply to Hime no matter what part of the equation you put her in. The MC should not thank Hime because Hime is the one who was talking shit about her. Hime is one of those fake friends. So what I have to say overall about your statement is hell no. Thanks for coming to my TedTalk ( ̄へ ̄)
No, that girl make the MC seem bad and fooled people into having the wrong perception of her, this preventing any friendships from forming. She is the fake friend, you don't thank fake friends no matter what, even if those fake friends unintentionally did something "good." Instead you tell them to fuck off and do the same onto those who didn't give you a chance and you go off somewhere where you can actually make some good friends. Then you love a Gucci life without the fake snake

Because Hime got rid of all her fake friends. Like what good friend would take slander about their friend from some intruder? If some girl just waltz into my friend group and starts talking smack about one of my friends, she's out. I don't care how cute she acts or how wide her eyes are. Any real friend would've stuck up for Anise.