<human>: Can you give me the gist of the text in a nutshell?

Ok so I decided to log into my gf's facebook today because I was curious what she talks about with who, and more so because she did some shady things that I thought weren't at all a faithful thing to do.

So I log in and i click on the messages tab and for some reason I click on this one guy's thread. The conversation she had with this guy, btw it isnt the guy that this is about, happened a month ago and we were together on that day. I read through some of the stuff, not all because i did't have the patience, but i read that she was talking about her coworker. She had told me about him before and telling me things like he always makes her laugh and he picked her up ounce and was walking around with her on his shoulder and blah blah blah. 

Anyways, I read through and she was talking about how she found him really cute and was wondering why he didn't like her back and that she liked him and that he was cute and she tried flirting with him. She said he tried to "touch his beard and flirt with him the next day" and that just made me really sad and angry.

What do I think of this?? I told her that we needed to talk and I told her about the situation but she doesn't know that I logged into her account and saw this.  Am I wrong for pretty much breaking her privacy but finding out this? What do I do now?
<bot>: I log into gf's facebook and find out she had been flirting with coworker she liked. Am I a bad person for that? What do I do?