A bad situation. I need help please :(?

My advice is to ask her if she did it, don`t say it was him who told you say it started to spread around. If she threatens to tell your guy best friend the secrets she`s obviously not your best friend. If you have confronted her and you know she is going to say something, tell your guy friend so he hears it from you. Tell him you were annoyed as he wasn`t being nice and just had to blurt it out to someone close- or at least you felt you could trust. Then you should hopefully all be able to patch things back up again and maybe forgive and forget :)