I figured I’d update this now that I’ve made my decision. I’d like to thank everyone who commented for taking the time to help me. The college search was admittedly one of the hardest periods of my life, both because of the incredible offers I got and the ones I didn’t.
As the last part of this post demonstrates, I was suffering from pretty low self-esteem when I made it. While UCLA was one of my dream schools, I was also hoping for other top tier universities (e.g. Stanford, Harvard… those types). Even though I knew my chances were slim, I let myself get pretty hopeful after my initial offers came in. So, of course, I was devastated when each of these schools rejected me (save Cornell, where I was waitlisted).
The thing that was the most damaging, strangely, wasn’t that Stanford turned me down - I had prepared for that for some time - but that USC did. I didn’t really want to go to USC, but I wrongly assumed that I would be admitted there because I got into UCLA and Cal Berkeley. Even more, so many people I know who I thought were just as qualified as me were rejected from UCLA. This led me to believe that I had gotten lucky with the top-ranked publics, and that I was bound to be a C-student if I went to UCLA.
After talking to a lot of people at each of these schools, however, I realized that this didn’t have to be the case. While UCLA will likely be more difficult than CSULB, there’s no guarantee that I’ll be top of my class at one and not the other. The saying is true: it’s not where you go, it’s what you make of it.
It was really difficult to pass up the amazing offers I got, but I knew that I had to make the choice that would be best for me in the long run. As you can guess from all the hints in this update: yes, I will be joining UCLA’s class of 2022! I am truly excited to be going to a school that genuinely makes me happy and motivates me to be my best self. While I don’t know what the future holds for me, I have a feeling that it’s something great. Whatever challenges I may encounter, I at least know that I am following my dreams and doing what feels right. Thank you everyone for helping me reach this state. Even though this thread was the whole reason I joined CC, I’ll be sticking around to help other students achieve their dreams. Hopefully I can help someone the same way you all helped me 
-R.