I have a question ladies about girl code

So there was this guy that my friend was talking to the beginning of the year (I heard about him periodically about how she was excited about him etc) things never wound up taking off between the two of em, they never dated but they did have sex 3 times, he stopped hanging out with her because she got too involved too fast and he wasn’t feeling it...well fast forward to a month ago I started chatting it up with this guy, super awesome, we clicked instantly. We were talking for about a month when she noticed us commenting on each other’s posts and she flipped on me... come to find out it’s the same guy she was into months prior. (I had no idea) Well now she wants me to cut him completely off, drop him from social media, block him, and even told me to be rude to him about it, tells me I should have known that was the guy she was into months ago (idk how I was supposed to know she talks to many guys)....now I’m torn, i really like the guy but I don’t wanna lose my friendship...is this girl code if she was never dating him? I’m sure I’ll get all mixed opinions on this...just hand it to me