Apologize for bad behavior caused by hurt feelings with this breakup goodbye letter for the end of a relationship.
Dear {Recipient},
This breakup has been hard for me. That is the only excuse I can give you for my poor behavior. It may not sound like enough of a reason for {hurtful behavior}, and I know that it probably isn't. I just want you to know that I was upset and angry at the time, and I am really sorry that I allowed those emotions to take over. I'm sorry that I hurt you.
I've been doing a lot of self-reflection and I think that what I was trying to do was to see if I could get a reaction out of you, because that would indicate whether or not you still cared about me. I know that that might be selfish, but it was simply because I miss you and I feel sad and confused a lot these days.
I hope that you can not only forgive me but understand where I'm coming from and not think too poorly of me. Since I am unhappy with my behavior, I think it would be best if we ceased contact with each other, at least for a while.
Please remember the good times we had together and good luck with whatever you do next.
Sincerely,
{Sender}