Post in here [comment or entry, doesn't matter] who you hate and who you like. If someone finds out that you dislike them, then you can either never speak to each other again, or work out your differences in private. If you're friends, then... good.
This way there won't be any people thinking other people are on their side when they're not, or any more bullshitting to keep on people's good sides. We'll all know who hates who and that won't be a big deal.