So for context, my friend (Fanta) has been dating her boyfriend for a year or so and recently she found out he has been cheating on her for a couple of months with a mutual friend (H) via another mutual friend ill call Sprite and Coke. Now Sprite was someone Fanta would talk to about all her relationship problems, and Sprite has also been there since the start of their relationship, so imagine how she felt when she was the one to find out Fantas boyfriend has been cheating on her all this time, and with a mutual friend that is in the same circle as them.. I mean the first time I heard about it they were both crying!! So naturally this sets a rift between their friendship with Fanta, Sprite, and Coke telling all their friends in said circle about what H did and they all started to distance theirselves from H because obvi...

Now here is the problem, unfortunately, Fanta has gone back together with her ex-bf... (who is a bitch btw) and this seems to break her friendship with Sprite and Coke because they were the ones who Fanta vented to during the breakup, they had listened to all of her complains, all of her problems, they gave her advice, etc. but not even a month in, she gave in to the temptation of her ex, and now Sprite, Fanta, and Coke are not talking to eachother, which is where I come in.

I'm a good mutual friend with both Fanta and Coke, and Fanta has been running to me because she doesnt have anyone else (other than her bitch bf) to talk to, and Coke has also been giving me their side of the story, and honestly I am on Cokes side. It seems pretty clear to me that Fanta doesnt value her friendship that much as she got back with her ex so quickly even after all of the help and advices Sprite and Coke gave her. I mean if I were in Cokes position I would be pissed too. But then again, I can't just ignore Fanta because as I said, she doesn't have anyone else. BUT I am so annoyed at her and cant help but to berate her everytime she's near. So what should I do now?

Also sorry for the grammar and shitty storytelling, English isnt my first language.