So, I had a falling out with one of the girls in my ground of friends the sometime in senior year. (It was, come to think of it, about who was taking who to prom - specifically about who she thought I should or should not go with.) She got VERY angry about it and decided we were never speaking again when I tried to stand up to her about it quietly. She went and told all the other girls in our packet friends a distorted version of it and they all sided with her. One which had been my best friend for years before that, most of these girls I'd known for years before she even came to our schooll They all stopped speaking to or acknowledging me. Was it painful at the time? Oh, hell yeah.
I ended up having the best senior year because of that.
I hadn't realized how isolated from everyone else in our class I had to come by hanging out with this pack of girls (that she had slowly but clearly become 'the ruler' of). It really wasn't apparent to me what was going on until I started seeing it from the outside, how she had grown to influencing and being in command of our opinions and actions. And how docilely we were going along with it, in fear of conflict I suppose.
I definitely hadn't realized how much hanging out with them had influenced not hanging out with other people in a very subtle 'oh, they're too redneck/uncool/not in the right classes/not sporty enough/whatever kind of way. I never thought of myself that way (because we weren't the 'cool, popular kids' we were more the sporty types) but it happened in such a creeping, slow way hanging out with them.
Senior year was great. We had a ton of events that second half of the year and I hung out with and reconnected with so many people I otherwise would not have. It was so enjoyable. Fun. No stress. No constant pressure on always doing the right thing or dressing the right way, only going to the 'right' people's houses. People being upfront and transparent and kind with each other instead of snide and cutting and hurtful games and subcliques within the clique. GOOD people, a much more diverse group of interests.
I never even realized what she had done to us until after it happened and I had some distance on it and looked back. I feel sorry for my old friends who were still trapped under that...whatever it was. Anyway, if it's any small consolation, it sucked at the time but it really was one of the best and most educational things I went through. It served me well later on in my life being able to recognize that kind of thing.
TL;DR - finding out one of my high school friends was an Alpha bitch who was manipulating us was the best thing that ever happened to me