I hear ya, Maven.
I got sober in the last half of my 20s. The first half was a nightmare. I mean, I thought I was having fun for most of it. But the truth was, I was angry, hateful and scared, and I blamed everyone else around me for it. I'd had a major mental health episode when I was 17 that carried on for a few years that I was never treated for (lived in a tiny town, no psych help there, plus I was living at home and my parents didn't know how to help me either) and I really had no clue how to live life. I worked, I got loaded, lather, rinse, repeat. I dieted, I acted out on my ED (bulimia), I moved around a lot. Lived in mutually abusive relationships. Increasingly spent a lot of time isolated. Became a birth mother. My 20s were lonely. Nobody should have to live their 20s like I did.
I too wish I could go back, though at least I finally see how the things I did then and the experiences I've had in life make me the person I am today. A lot of my anger I have directed into determination to get back on track with school and other things in life and find out how to really live.