What are some of the worst 'in-transit' arguements you've witnessed (or even been invovled in)?

I've only ever seen one, LHR-SIN an elderly english couple began arguing during the night. The woman let the man have it, complaining about how he never has sex with her and how the only reason he was with her was for the cooking and cleaning. It lasted over an hour, and by the end of it, she had pretty much divorced him.

Suprisingly, the FA kept serving her alcohol (despite being intoxicated) and didn't comment about the fact that she was swearing her lungs out - I was 7 rows back and could hear it over my movie.

Never witnessed any violence though, which is suprising given the shortage of overhead storage on many flights.

P.S. I know there have been many similar threads, but I can never get enough of reading them