I met this girl I'll call Katie at a school event about a year ago and we really clicked and soon made things official. I understand that I saw things partly through rose colored glasses, but I really, really liked this girl to the point that I started thinking she might be the one. We just matched well on every level, have similar hobbies, but importantly I thought she was a really good and kind person.
Now something happened that really made me reevaluate things. We were sitting in bed and she was texting and laughing about something. I glanced at the phone and saw the Tinder profile of a guy, which made me think wtf. When she went to take a shower, I am not super proud of this, I admit I snooped given what I thought I saw and checked her phone.
When her phone opened up it turns out that she wasn't on Tinder, but rather on a group chat with some friends and the Tinder pic was a screenshot. Of course that was a relief, but the rest of the context was just as bad in some ways. The group chat was basically a one-topic channel, where the theme was roasting the guys they hooked up with or were dating. And it was very explicit, talking about specific guys, together with their pics and joking about their inadequacy in bed or even how ill-endowed they were. As far as I scrolled I wasn't featured on there, but I saw Katie herself write really mean comments, e.g. about a guy her friend was with who got emotional during sex, basically calling him a pathetic loser.
I was just shocked to read those comments, because it seemed so out of character for her. When she got back in the room I fessed up to the snooping and confronted her. Surprisingly she wasn't really mad, but she also wasn't remorseful in the least. She said the chat was with her closest friends and they always talked about everything. I told her I thought it was really fucked up to talk this way about other people, especially since it wasn't just randos, I recognized a few mutual friends discussed on there in an explicit way and I am sure they didn't consent to that information being discussed. But again she got really defensive, said those were her closest friends and what they talk about is their business. I asked her if she talked about us as well, and she refused to answer.
The conversation kind of tapered off at that point since we both realized we were too emotional and not getting anywhere, but I still feel very uncomfortable with the situation. I am afraid to be overreacting, but I am very seriously thinking about ending the relationship. I can't believe I am dating someone who thinks it's ok to treat other people this way and join in the public humiliation of people who did nothing wrong.
But I would like some outside perspective from others if they've been in any kind of similar situation and/or if they think I am blowing this out of proportion.
tl;dr: My GF is part of a kind of group chat where they roast guys they've been with, including by sharing private information. The situation makes me extremely uncomfortable to the point that feel I want to end the relationship.