This show tries to reconcile two ideas: Being a lighthearted romcom while dealing with the topic of mental illness. It ends up being mediocre at both.

Starting with the romcom aspect: The actors are doing a good job and the story flows well, although there are a lot of story points that go nowhere. Some of the subplots I found uninteresting and the characters sometimes annoying. The soundtrack is good, untypically for kdramas there is actually western pop mixed in. The main story relies heavily on the before mentioned mental illness theme.

And this brings me to the second aspect: the mental illness. And this has multiple issues.
First, it is ubiquitous taking away from the impact: almost all characters either suffer from mental illness or are psychiatrists or both.
Second, a lot of those afflictions go nowhere and feel like a gimmick.
And the third and most problematic point: the show is staying incredibly lighthearted. People will talk about the issues and will cry a lot. But only once in the show I actually felt an impact from them. And that was from a short episode of a side character couple.

So in the end the drama fails at what it wants to do, but overall I still enjoyed watching it.