Okay, so this is probably one of the great underrated anime out there, and I know that not everyone likes or is fine with BL, but what makes this show amazing is that they actually made a metaphor for depression - crystallization syndrome
The main character, Tamari Ayumu suffers from it, random parts of his body crystallizing whenever he feels anxious. He hates this, and he hates himself, easily believing that no one would ever want to be friends with a 'crystal'. The other character, however, is Onihara Kouya, the homeroom teacher, who, apparently, likes crystals. Basically, the whole story revolves around the two, and that the entire show is a metaphor for having someone who can accept you for who you are and sees the beauty in something that you consider a flaw or a weakness.

Another from the Kono Danshi series is This Boy Caught A Merman. Like the other movie, the protagonist has depression issues and focuses mainly on the protagonist's internal struggles with himself and loneliness. Kawauchi Shima has been raised with many 'labels' that his parents other people put on him. He succumbed to these, hiding his true self and feelings while growing up to the expectations of others. Because of this, he has felt terribly lonely, as no one knew the real him.
Little did he know that someone like that would come to his life - Isaki - or so, he was named by our protagonist. He keeps Shima company and tells him that he should have more trust in the people around him, that he shouldn't be afraid to show the real him, so that he could be loved for who he really is and not be so lonely anymore.