For me it’s detailed describtions about people’s dreams.
Not only doesn’t your story make any sense, but you’re also telling me about something that didn’t even happen. It’s kind of like telling about an event, and then ending the story by saying you just made it all up, except with dreams you begin by telling it’s all made up. I’m already not interested before you even started.
People talking about wanting to lose weight or dieting. It’s one thing to say “I’m going to skip dessert because I’m watching what I eat” but more often than not, it turns into this dark, self hating thing, e.g. “I gained so much weight over the holidays, I can’t believe I’m up to X lbs, I look so ugly.” Women especially seem to bond over these conversations and it makes me really uncomfortable and sad to be honest.