Depression hit me later in my life, and I think it's the opposite. Loneliness caused me the depression, but now depression is causing more loneliness. I do believe I have ASD and SD (and ADD). For the diagnostic procedure, actually they told me if no one comes with me they won't do it. They didn't say it's preferred. In the letter I received they wrote this note in capital letters to emphasize it, and the person I called when I took the appointment emphasized on this as well. I think it depends on the hospital, but this one seems to have this policy. I will try to discuss this with them if they would accept doing it for me without a company, because I must do it.