Help- ADHD/existential depression/something else?

You should try an anti-depressant my friend. I just finished a 7 month adventure on one type called Lexapro. I was just like you and after a few weeks of taking it, I felt like the real me. I also wen't through group therapy which sounds lame but it actually provides a ton of relief when you get to talk to people that are having the same experiences!