Is AUTHOR wrong in the post ? POST : So to give some context, I've been friends with this girl, let's call her Clara, since I was roughly five, our parents knew each other, and we grew up together. We were tight right up until we graduated and went to college, along with three others who formed our tight knit friend group. Two of the others went to college in the same place as me, and the third stayed in our home town and started working, while she went to a college about two hours away. We still talked a lot of Facebook, and as none of us were too far from home and spent summers at home there were many opportunities to hang out etc, however, in the three years since we have started college we have seen each other only a handful of times. 

It all seemed to escalate after she left my 21st birthday after about half an hour, stating that her lift home was leaving and she had no choice, however, other friends coming in late saw her go to a night club across the road with her boyfriend. Shortly after, another girl in our friend group found out her girlfriend had been cheating on her. Rather than support her friend, Clara became close to the girl who had cheated and reported our conversations back and forth with her. 

Eventually I got drunk, and was with the others for a night out, which Clara had declined to come to. I found they all felt like they had not been close to her for some time, and they felt uncomfortable having her in the Facebook group chat as they felt they couldn't talk openly in it any more. I created a new chat without her in it that night, and we let the other one die. The only communication in it after that was her asking us to go to her birthday, which none of us committed to. Shortly after that she left and hasn't spoken to any of us since. 

Am I the asshole for being the one to make the move that ultimately led to her being iced out of the group? As the one who's known her the longest I feel like I at least owed her a conversation to her face about it, but instead we went behind her back. 

TL;DR: am I the asshole for effectively cutting out ab old friend who'd grown distant during college from our friend group ? 