Responses
Unfortunately human psychology is very complex. Many problems look simple but they have great depth underneath.
Don't worry whether you can't understand. But even if you do, it's not wrong. Cause trying to understand doesn't mean you're excusing it.
I think the magic of this webtoon comes from the fact that based on your opinion of Hana and Jun's ex, you can guess what type of person you are. Ofc being abused or having low self-esteem doesn't justify your actions but they can explain them. Still I can't empathize with them cuz I was raised by a loving family and I've never went through something that traumatic so it goes beyond my compression how you can try to hurt someone as cruelly as they did because you have a big wound. But I can recognize that I have this opinion bcs I'm "privileged" (which shouldn't be) to have a loving and accepting family. Reflecting this thanks to this webtoon is what I liked the most of it.