I think it's a logical ending, because the son gave up his life for taking revenge to finally knowing his father was the one that ordered to murder his mother, and the man remembered everything that happened and couldn't keep living knowing what he had done
I recommend you to watch: Weightlifting Fairy Kim Bok Joo, I'm Not A Robot and My ID Is Gangnam Beauty. These are really amazing and gripping dramas. I'm also in a show hole in this moment but I try to get over it by still watching the shows that i didn't finish yet. If you want new interesting dramas go to my custom lits and look into Blow Your Mind, the plots are so good and would make you to watch it till the end.
This is really unexpected had good laughs especially when she’s being cornered by her own situation of dealing…
I've just finished and I'm also really confused about the ending. I've never seen a drama like this before and it was quite flustering for me and after knowing that she was lying I was like ... "she better not end with any of them or I'll be really mad" and yeah I'm so mad about it. AND SHE DIDN'T EVEN TELL HIM THAT SHE WAS DATING THE OTHER TWO *sigh* I'm stressed