This whole thing might sound a bit silly, so bear with me. So, I always hated myself. I was an EXTREMELY late bloomer (I legit got my first pubes when I was 16). This killed my self esteem. I looked like a child, I didn't hit 5 feet tall until I was 16, and I didn't hit 100 pounds until damn near graduation of high school. Because of this, I had no confidence in myself. I'd see everyone around me with full beards and getting all the girls they could ever want, yet nobody wanted me because I was a literal fetus. I had tons of friends growing up and would constantly go to parties because I hated being alone. It's not like I was an unlikeable person, in fact I was friends with tons of girls that were extremely pretty, but that's it, I was just friends with them. I was at the lowest point of my life, and then my friend died, causing me to be in an even deeper rock bottom. I had no confidence, no happiness, and I didn't even know who I was or who I wanted to be. Right during this time, I met my ex. There was an instant connection and we got along so well. She made me feel confident in myself, she gave me a reason to wake up, and made me truly happy. Unfortunately, because I was essentially an empty shell prior to meeting her, my entire reason for life was her. The relationship was perfect for the first year or so, but after that, a lot of my issues started becoming prevalent. I was young, immature, insecure, and inexperienced. Well, we both had issues, but I just dread mine a lot. I would like to be clear that I never cheated, abused, or yelled at her in any scenario, but I would often get jealous over trivial things. I'd get super anxious, overthink, and it definitely wasn't a good trait. Eventually, she would break up with me, and I didn't take it well. I'm not going to get into how horrible my life was post breakup and stuff because that's not really what this is about. Well, it's been 3 years and I have had to learn how to live my life without her. I was incredibly obsessed and dependent on her, and figuring to be independent was no easy task. On the bright side, I have learned so much about myself and have started to become a person that I am actually proud of. I'm much more confident, I'm much happier, and I'm just a kinder person. It might sound corny, but I want to positively impact as many peoples' lives as possible, even if that's just me telling some random guy on the street that I like his shirt! The issue is that I feel like I'm being held down by my past. I understand that those are my mistakes, and I deserve to live with them, but I can't help but be sad over the fact that her memories of me are probably of the end of the relationship, which would be very negative. I deeply want to reach out to her just to apologize for my past, and wish her the best in life. She wouldn't have to respond, and there wouldn't be any other motive other than saying that I'm sorry. I can't tell if this would be dumb or not. I mean, it's been three years. We've both graduated, moved on to college, and have probably went through multiple other relationships since then. What if she forgot about me? I feel like if I send that message she might just wonder who the fuck is even texting her, but at the same time, we were together for a while, so I feel like she wouldn't think that (maybe?) I'm kind of just rambling at this point, so I just want some advice from anyone.

TLDR: I feel bad for my immaturity with my ex, and want to apologize to her to be at peace, but I'm unsure if that's smart.