Opinion about Melancholia Alltag von überall

As asked in the title, I would like to know your opinion about Melancholia.
I'm not talking about the Medical meaning of Melancholia that would characterize a deep and worrying depression.
I am more talking about the common sense/popular definition of Melancholia, which is more likely linked to a persistent unhappy/sadness state without any threat to life.
Just a state in which you would feel this persistent sadness and be used to it; leaving with it, waiting for her to come back in the dark evening and appreciating her companionship/presence.

Have you ever heard about this ?
Do you know someone experimenting it ?
What do you think about ?

I think that Melancholia is the concubine of art, and creativity is the "natural child" of it.