At first, Part2 felt empty to me. Because we are watching her getting revenge. Part1 was mostly about her teasing and psychologically torturing her bullys. BUT her revenge was so good!
It displayed everything i expected!
There is no affair, getting cold feet at the last moment, Dong-Eun feeling guilty about revenge, betrayal plot. That’s all i needed.
Even though her first 38 years were living hell, she met lot of loving people along the way whom showed Dong-Eun heaven is still on her side, god sometimes mistakes too.