Dear Ex-BFF,
Let me start off by saying that I am so sorry. We aren't friends anymore and it's my fault. I'm the one that shut you out, I'm the one that walked away from our friendship and I am truly sorry for that. That doesn't mean that I completely regret my decision to not be best friends anymore, because I believe that everything that happens is supposed to happen, and that for some reason we weren't supposed to be in the next chapter of each other's lives. But I do regret the way I handled everything. I regret the way that things went down and I am so upset that we are not only just not best friends anymore, but that we aren't even friends. We're complete strangers. We haven't spoken a word to each other in years and it completely breaks my heart.
I remember when we didn't go a day without talking, not even an hour without talking or texting unless we were asleep. I remember all the sleepovers, all the inside jokes, secrets about boys, secrets about friends and parents and school, the gossip, double dates (or more often, me third wheeling with you and your boyfriend, even though I never felt like a third wheel), hanging out doing nothing, everything. We had some great times and I don't want you to think that I just forgot about them and I never think about them. I think about them all the time. I think about what it would be like if we were still friends.
I doubt you will even read this, but in case you do I want to try to explain my side of what happened. I felt like we were drifting apart. We got a little older and our personalities changed a little bit, and we didn't have as much in common anymore. We started hanging out with different people, still hanging out with each other, but making new friends and hanging out with them more than each other. For me, it got really hard for me to be friends with my other friends and you at the same time. I felt like I had to choose between them and you, so I chose them. It was high school, and you just didn't seem to fit into my life anymore. And I feel awful about that. I felt bad about it then and I feel a lot worse about it now when I think about how it must have made you feel.
I know that there's nothing I could say to make it all better or to fix what happened. Everything happened how it happened and I can't change it. I know you probably hate me now, but I just want you to know how sorry I am. I'll always love you and keep the memories we had and remember that you were one of the best friends I ever had. I hope life is going well for you and I hope that this letter makes you feel a little better about our friendship. I miss you.
Love,
Your Old Best Friend