So I am a teenager and I work at a barn and have a good relationship with my boss who owns all the horses I take care of. Well one day I was with my friend and fellow coworker, Ill call her E, playing around with one of the horses when my boss comes to the barn with a friend. I take one look at this "friend" and immediately recognize him as guy who had cheated on my best friend's mother (this was a few years back and they ended their relationship then). This man, who I'll call B, recognizes me and hugs me, asks how i've been doing, etc. Well, my boss can act pretty flirty with people so I could not tell if she was in some relationship with him or if she was just friends with him.
Even though I decided her dealings with him were none of my business, I couldn't stop thinking about what he had done to my best friend's mother and, in a moment of a complete lack of self control, I told E what he had done. She was surprised and I felt bad for telling, but we just kind of left it at that because we thought that he might have changed and it's none of our business anyway.
Well, weeks go by and all of a sudden I get a text from her telling me that B has been hanging and and talking to our boss a WHOLE lot more and that she really doesn't like him and thinks we should tell her about the cheating. I asked her if he did anything to suddenly set this off and she told me he came behind her one day and started massaging her and acting really creepy, and now her mom is really mad and wants to tell our boss. E wants for us to tell the boss together about the whole situation.
Any advice on how to deal with this? Sorry about the length and the grammar.