So, a bit of a backstory here: this buddy of mine (for the purposes of this post, let's call him Red) has had a thing for a girl at his department (let's call her Purple), and while they are friends, she's made it clear she doesn't like him the same way (declined an invitation to a date before). She didn't let it affect how she treats or sees him, and he seemed to have been cool with it. I work at a different department within the same corporate structure, so I'm not too close with Purple, but do hang out with her and a few others when I chill with Red and he invites them along. 

Recently, another friend from their department got married, and surprisingly, she had invited me too. I figured it was simply due to my association with Red. On the day of the event, some of the bridesmaids had found me and abducted me to where the bride was. She explained that she invited me not because of Red, but because of Purple. Apparently she had a thing for me, and they asked me to ask her to dance during the party. I told them my unease due to the whole situation with Red and her. They tried to explain how Purple and Red were pretty cool with just being friends already (it had been months since she 'rejected' him), and they even tried playing the "For the Bride" card with me.

In the end, I told them I'd think about it, and escaped the room without saying anything committal. I was very much conflicted about it, but during the reception party, invited that Purple was sitting alone when most of her friends had gone dancing. Red had gone to try to ask her for a dance, but from what I saw, another girl had dragged him away, (I don't know if she replied to him or not) but he was on the dance floor with another girl. It was then that Purple caught my gaze, and in that spur of the moment, (out of a bit of awkwardness) I went up and asked her to dance. We spent most of the rest of the night chatting, and really getting to know each other, but I still felt conflicted about things. 

At the end of the night, another friend of mine came to tell me Red had left the event early, and were wondering what I was doing dancing with Purple and stuff. I didn't wanna tell him about what the bride had asked me to do, so I just dodged the question. He told me not to be an AH to Red. Purple has also started to message me privately, which she's never done before, even when we had each other's contact info from way before. I feel very confused and conflicted. So please, AITA? 