Your mental health is important. Your feelings are important. 
It's okay to not be okay. 
     This kdrama showed me that sometimes, one person is enough to drastically change how you view life. It also taught me that you don't need to always put on a happy face for other people, you don't need to be fine with things that are hurting you, because that will only make other people more insensitive to your emotions. Just like how everyone perceives Gang-Tae as tough and well-put, when behind closed doors, he's struggling with problems of his own. And how Ko Moon-Young always acts tough with other people, but when she's alone at night, her past torments her. 
     It's okay to open up to people, it will help ease the burden in you, and if you can't, you can always pray to God---He listens to us, and heals us over time.
     To everyone who's having a hard time with their mental health during these harsh times --- hugs! you WILL overcome it. You WILL eventually heal. Just don't keep all your feelings bottled up. It's okay to not be okay. Stay Strong!