A good thing gone bad

It's crazy to think about how an amazing memory can be trampled all over and ruined completely. When you're young its so easy to give your heart out and use your imagination. You don't think about the risks or the consequences as much as you do when you're an adult. You don't recognize when things change, but it still happens and you keep going day by day. Your mind changes, your heart changes, your body changes, and people change from experience because they gain knowledge. He was the nicest person I had ever known and he would go above and beyond for me if it meant helping me out or making me happy. We had fun together and we laughed together. We grew together and our friendship eventually grew into love. I always thought that it was a 1 in a thousand chance of finding your true love at 15 and being together for all that time, that was until I fell in love with him. I just didn't think I could be that in love with someone and have it last. Maybe that's what broke us in the end. He didn't trust me with his heart really and I took him for granted way too many times. I assumed that our love could withstand wild fire. Then before I knew it everything changed and we were enemies and our fights burned our memories leaving nothing but ashes in the wind. Something had just changed in us that neither of us knew coming until it bit us in the ass. We did and said things that were so tragically horrible, things we couldn't just say 'sorry' to and take back, though I wish we could have. I distanced myself from him and for a while I thought that we would one day be able to be friends again. Until he started doing whatever he possibly could to make my life a living hell, and he did, it worked, and I burned. He was the complete opposite from when I had first met him and the more he scarred me the more I realized that who he used to be was gone completely. That relationship taught me alot and it also scarred me, it made it hard for me to trust people and love again because he first changed my heart for the better, and then he simply ruined me. I felt like it was all my fault, I blamed myself for the way he changed and I still to this day don't know why. I had given him all of me but that wasn't good enough, I gained many insecurities and weaknesses but after time I healed and I used our experience as a reason to become stronger and wiser. It's been roughly two years and we get along fine now, but we will never be the same.