<human>: Can you condense the text into a few key points?

About 3 years ago I started noticing an increasing difficulty to focus and take in information, as well as as being in a constant state of brain fog/lethargy.

When I was diagnosed with ADHD over a year ago I had hope. There was a light at the end of the tunnel. I was failing out of a shitty university, I had no social or personal life, and I was spending my days barely existing and unable to function. But this was just due to my condition! ADHD diagnosis and treatment was going to help me fix my life!

No.

Psychiatrist tried me on 3 different medications. None of them worked. Psychiatrist is no longer sure I have ADHD. Wants me to get a sleep study done, plus some ridiculous neuropsychological assessment. I can't afford either. And even when/if I can, it is doubtful a sleep condition can explain my issues. My psychiatrist is basically saying: "I don't know what's wrong with you". Scary stuff, because I was kind of clinging to the hope that he did.

My life is pathetic. I would be ashamed if I wasn't so scared. I'm 22 years old. Everyone I know is finishing their degrees at good universities and getting jobs. I have now failed out of a shitty university, and I'm close to doing the same at another. I'm lonely, I've never had a girlfriend and I have few friends. I have nothing to show for my life, I basically don't exist.
I HATE wasting my life, but it's just so hard to do anything. I used to be really smart, just terrible with procrastination. Now even when I try do something I can barely think, and the brain fog/lethargy is so constant and debilitating.

I'm not entirely sure why I'm posting this. Maybe someone has advice. Thanks for reading.
<bot>: My life is pathetic and empty. Being diagnosed with ADHD gave me hope, but treatment failed. I'm so lost.