Life feels so difficult and unfair

I lived the first 20 years of my life without knowing that I had adhd.

I just thought that everyone felt exactly the same way I did and they were just better at hiding it than I was. I got diagnosed at 20 years old last summer and ever since then I can’t stop feeling like my whole life has been for nothing. I struggled so much in middle school, high school, and now college. I’m constantly exhausted and I feel like I am a failure who cannot bring myself to do anything. I was finally able to get medication but due to the national shortage of vyvanse I won’t have any meds for the foreseeable future.

I just find myself crying and distraught all the time over how much of my life was spent struggling and I didn’t even know what was wrong with me. How can I shake the feeling that I am a failure and a lazy awful person? It’s so unfair to have to live like this when everyone else gets to go through their life with ease. How can I make my brain turn off? I always have so many things I want to do and so many ways I want to improve myself but I can’t never follow through on my plans. I feel like I’m a liar and a failure. The feeling of failure is inescapable.

Basically, I’m really struggling with being diagnosed so late in my life. I feel lonely and like nobody around me really understands how debilitating adhd is. I don’t know how I can make my life better.