There aren't a lot of films like Dr. Bird's Advice for Sad Poets, but there are even less that have endings like it. I think most filmmakers feel an obligation to fit into the expectations of their viewers, but DBA almost always did the opposite. I often found myself thinking, "this isn't allowed", at every turn. This wasn't necessarily a bad thing, more so just unfamiliar territory.
The world in this movie doesn't exist, by a long shot, and yet the literal feelings of James and all of the other characters are very real. Although surrealism seemed to be the main avenue for telling the story, that didn't stop it from taking itself seriously, especially as it neared its end.
I initially left feeling heartbroken because most films give their audience the courtesy of leaving them feeling fulfilled, but since DBA gave that element of escapism for much of it's running time, it only made sense they would bring you back with a message of reality, a wake up call of sorts by its end.
The reality that for most of us, who we are around other people/for other people isn't necessarily who we are, because we don't even know who we really are. And even though things don't always go our way at any given moment, we can't hold others nor ourselves back because of it. We have to continue living and just allow it to be apart of us without letting it define us, so hopefully one day, we can get to a point where we're happy with "who" we are.