When I was diagnosed with depression when I was 16 it was amazing. I knew something was wrong, that I had more than just a string of bad days. I knew if I asked for help by saying, "oh I'm depressed" people would respond with, "well everyone becomes depressed sometimes." But when I was diagnosed I knew what I was going through had a name. Stigmatization of mental illness is still an issue, but I could clearly say that I'm worse off than just sad. At the time I had a wonderful therapist who used a diagnosis to aid me in received help, not in hindering me as a person.
However a year later I saw a therapist who was testing me for ADD and that's all I was, a diagnosis. I only saw him long enough for him to test me and be diagnosed (the *** didn't tell me he was going to diagnosis me, I had to find out other ways).