What I loved:
-Park So Yi as Bok I Na. She is a terrific young actress, I've loved her in everything I've seen her in, and am looking forward to her growth as an actress.
-The youth romance of I Na. I would have liked to see more of them.
-Oh Man Seok's character of Gi Ju's father. What a calm, warm and lovely character.

What I didn't like (not in any particular order):
-I have liked Jan Ki Yong in other works, but I didn't think he did a good job here. He didn't look depressed, he looked drugged. I felt like he was just moving through the drama. I got no emotion from him.
-Chun Woo Hee looks just like Song Hye Kyo to me. Since I'm often not a fan of SHK, I struggled.
-The timeline was all sorts of a mess. For me, the fact that she was there showed that she survived in the past. No matter how they tried to explain it, it didn't make any sense to me.
-Did the ML and FL hate each other IRL? They had absolutely no chemistry with one another and didn't like each other for so long, I never bought them as a couple.
-Can we talk about amazingly bad haircuts of Gwi Ju and Grace?
-The weight loss story for Gwi Ju's sister. We see some of her struggle, but her massive weight loss was overnight.
-Pretty much all the characters other than the couple I mentioned. Her family (and she) were awful! I get that they were swindlers, but I never really saw them turn around until the last episode. Same for his family. I just didn't like them.
-Repetitive, repetitive, repetitive script. Enough with the flashbacks.

For me (please remember, this is just my opinion), I was extremely disappointed in a show that I was so looking forward to watching.