I love the drama and the acting skills of the cast. Just a piece of regret to the things that might change if they chose to fight for each other and not let the ego reigns in their way.

Story : Deeply shows that marriage is not a joke so as love. Sometimes, we expect too much from each other and failed to look at each others capability. Also, best story that will help you realize someone's value, only when they are gone.
To let go is the safest way.

Acting : I looked for it because of Yin Ji Han, but Ms. Hong So Hyun also give rich acting skills. They both show few tears but the emotions will surely strike you and I do cried a lot, the story and its emotions was greatly shown and it hurts so much.

Music : I haven't noticed any music, just few melodies of instrumentals to coordinate with the mood.

Rewatch value : It's so heartbreaking, but I will still rewatch it.

Overall. The story is one of the best 1-shots. I am a fan of heartbreaking dramas, and the end is somehow fine to me, but if you are going to watch it. Prepare for unknown pains like you are one pf the characters. For Yi Han fans, try this one.