Complex sentence: Otilia leaves Gabriela at the hotel to go to Adi's mother's birthday, she's still visibly disturbed but stays and has dinner with Adi's mother's friends, who are mostly doctors.
Split into simpler sentences: Otilia leaves Gabriela at the hotel to go to Adi's mother's birthday. She's still visibly disturbed but stays and has dinner with Adi's mother's friends, who are mostly doctors.