Gosh I have so many conversations that would land me in a mental hospital if somebody heard them... Probably the most awkward was me and my friend talking about how pretty our nipples are... In our defense, we were drunk.
Having to tell a really good friend of mine that she smelled. It was horrible. I had to tell her because other's around us were saying things. Sadly, when I did tell her, she said she already knew! She was a really good person, and I hated to hurt her feelings, but she had to be told.