Glitterland by Alexis Hall is supposed to be a queer romance, that is how it is listed but that is not what I took from it. The passages in this book about depression both the usual kind and bipolar are exquisite. I am willing to bet that the author has intimate familiarity with it or did a hell of a lot of research.
As a suffer of dysthymia, (depression, mild and constant which sometimes slips into the nether world), I am familiar with many of the things he talked about. I was truly blown away when I saw words the described things I only had feelings about.
I suggest you read this and see if you can read about what real mental illness is