Olivia could have used her self-defense skills to fight Ethan, but she didn't want Isabella and Aaron to find out they were there. Otherwise, everything she tolerated before would've been for naught.

She wouldn't be able to live with herself if she caused Isabella to commit suicide out of shame. Cheating was wrong, but she didn't have to pay for it with her life.

Too many people had been hurt or killed because of her. Cyril's leg was still suffering from lingering effects after so many years