Sorry for the length, but please bear with me, and try to help me out. I have made many, many mistakes, and I'd give anything to make her happy. First off, I met this girl in High School, it started off as a mutual crush that we turned into a relationship on her 16th birthday. We took the relationship extremely slow, since it was both of our first real relationships, and since I was her first boyfriend. We really got to know each other and became inseparable, we used to celebrate "random day" where we'd bring little handmade presents and notes for each other, we'd write poems to tell the other person how much we love them. Unfortunately, I hate being away from her so much, I just want to spend as much time with her as possible, so being alone is terrible. She understood this, and it was never a problem because she always wanted to see me just as much. I don't know what happened, but somewhere along the line we got into some stupid fight, and it was as if we'd stopped being such good friends... I began to act really jealous when she would pay people more attention than she did to me, and I'd insist that she broke contact with them. It sounds terrible.. and it is, I was way too controlling. I was such a selfish, little kid... but my heart was always in the right place. I always wanted it to just be me and her through everything. And we were still so happy together despite the mistakes.
Unfortunately, every so often, we'd fight about something dumb, usually entirely my fault, and she'd tell me how she doesn't want to go out with me unless I change, and I always told her I'd try. But it was completely half-assed and I completely glazed over it basically. After these fights things would always start off fine, and then they'd become amazing, and then a fight would happen again, because I didn't even try to change. This happened maybe 3-4 times throughout our 4 year relationship. Two weeks ago, we got into a small fight, and she left kind of upset. I vowed to myself that I'd never take her for granted ever again, and that I'd grow up and get over my childish issues. The next day she acted like everything was fine... but then suddenly she told me she didn't want to go out anymore, and that she meant it this time, she was fed up with me.
I completely understand why she feels that way, and I don't deserve a second chance after all of the ones I just blew off in the past. But losing her has made me realize that I can't be selfish, I can't be jealous, I can't expect to hold on to something I can't be friends with. Regardless we have always, and still are, best friends because of how close of a bond we have. She told me that she wants to get over me, and that she can't have these feelings anymore, because it will not work. To help herself get over me, she has been making new friends to fill/mask the void.
Being completely honest, I no longer have the jealousy issues I once had, and I just want to show her that I can make her genuinely happy in the relationship and that I trust her with my life now. I understand that I made so many mistakes, and that she was kind enough to wait for me to change, but it took so much for the change to happen.. and it's all my fault. I don't want to treat her like that anymore, I just want to hold her in my arms again and protect her. I really ****ed this one up... we had planned on marrying and growing together. I did everything with this girl. I have already been through my "being clingy and depressed" stage, if I seem desperate she will never want to come back.. but even so... I feel like she's slipping away. I know that I don't deserve it at all, but I know I changed for her, and I know that I would do anything to make this work. I don't know what to do to show her that she doesn't have to give up on me just yet... and that we can be perfect again just like we used to be. I sincerely hope that giving her space will help her to realize how much she misses me.. even though we had our share of fights, we were still so in love. I know she still loves me, and I know the feelings are still there... but I don't know how to get her to trust that I'm a new person. I need help... I know it's so late for the change.. and I'm so sorry to her that it took this much, but I just wish she'd give the real me a try before giving up completely on this. We both put so much into the relationship, and all of our happiest moments are shared together. I pray to god that me and her were meant to be, and that I didn't mess this up beyond repair.. I know, from the bottom of my heart, that I can make her happy and be the change she wanted.
Is there a best way to approach this situation..? A way to maximize the odds of her giving this retard one last attempt..?