Technically this lady was sitting with me but a couple of years ago I was visiting family and I was at an aunt's house for New Year's Eve. Everyone else at the house went to bed early but my uncle (by marriage) decided to drag me outside to start a bonfire at an empty plot across the street. A lady stumbled drunk from some kind of a small house party and sat with us; seemed as if my uncle knew her and greeted her accordingly.
Then he left me alone with this woman, and we sat in awkward silence until she nodded off. Then she started sleep-talking.
It sounded to me as if she was bouncing back and forth between dreams/recollections, but they all sounded like they were addressed to her partner. Sort of (really soft) mumbled yelling, one-sided arguing, that sort of thing. Stuff like, "Why aren't you picking up the phone? I called you like 6 times... Don't give me that bulls***... Where have you been... Hanging around with that woman..."
She eventually woke up and rejoined the party. Never saw her again.
Tl:Dr overheard a drunk woman sleep-arguing with her unfaithful(?) partner.