Please explain - why are sad endings actually a good watch?

 Eternal Flame:

Sad endings, no matter if drama, movies, animes, did trigger depression. I felt like falling even deeper into an abyss than I was already anyhow. Took days sometimes to get over it. That's why I was so curious as to why some say: Sad ending: no worries... Lol

I will try to turn the focus away from devastation in a sad ending and engulf myself on their journey. And maybe willing to face sadness will help me get emotional stronger in a way. I wonder.

For me, when sad endings trigger depression, it is likely because I am already dealing with an underlying case of depression. In other words, it's not the sad ending that causes the depression. The depression was already there; the sad ending just exacerbates it, given that depression makes one more susceptible to negative emotions. 

Therefore, watching sad endings doesn't necessarily make me more emotionally resilient. What I have to do is deal with the underlying depression that is already there. When I am not depressed, I'm quite emotionally resilient and I can tolerate all kinds of endings. However, I avoid sad endings because in general I just don't like them. I guess they don't go with my personality. I don't like sadness, I don't like to cry and I don't like to see people (esp characters who've grown attached to and love) be devastated and cry over tragic events that have befallen them.

Because what matters is the journey and not all stories can have a happy ending. I myself prefer a happy ending, but there are stories where a happy ending would be unrealistic.

 Shadow:

@ Eternal Flame 

I always look in the comments if the ending is going to be a happy or sad one before I start watching it. If you would, please spoil me. I would appreciate it very much on my now new discovery journey of: How to love dramas with sad endings :-) 

 Mr. Sunshine( It's a good example of a bitter sweet  ending)

 Empress Ki

 The Princess Wei Young

Thanks for the recs.

I will probably start with Scarlet Heart and then move to your list...

I'll keep in mind that it's more about the journey ;-)