Please dont feel like i’d never respond. I always respond. However, the topic you’re asking me about isn’t really my specialty. I’m AWFUL at relationships. Complete shit. But if i were in your shoes, i would skip the letter and attempt to show her raw emotion. I would ask to have a talk with her and take her someone secluded- like a private beach or park- and just bear my feelings to her. I would attempt to explain my love to her to the best of my abilities and explain where i know i went wrong and how i’m going to try to be a better person. I think intimate chats are more effective in getting to the bottom of a problem and showing that you care. You have to really make an effort to change though, don’t give her false hope or drag her on if you’re not ready to change. It is COMPLETELY okay if you as a person are not ready to change. Sometimes we just aren’t ready for the commitment it takes to morph ourselves. You might want to also have an open chat with yourself to see where you stand. Idk if any of this made sense or will help, but best of luck to you.