I'm sorry for not being the best boyfriend. I'll do better
I want to take this opportunity to express my sincerest apologies for not being the best boyfriend that I could have been. I realize that I have made mistakes and have not always been there for you in the way that you deserve. I am truly sorry for any pain or hurt that I may have caused you.
I understand that relationships require effort, communication, and understanding from both parties. I acknowledge that I have fallen short in these areas and I am committed to making things right. I want you to know that I am willing to put in the work to improve myself and our relationship.
I know that actions speak louder than words, so I am determined to show you through my actions that I am serious about making things better between us. I want to be the best partner that I can be for you and I am willing to do whatever it takes to make that happen.
I understand that trust is something that is earned and not given. I know that I have let you down in the past, but I am willing to work hard to earn back your trust. I want you to know that I am committed to being honest, open, and transparent with you moving forward.
I want to be the person that you can rely on, confide in, and lean on during both the good times and the bad. I want to be your rock, your support system, and your partner in crime. I want to be the person that you can count on no matter what.
I know that words alone cannot undo the mistakes that I have made, but I hope that you can find it in your heart to forgive me. I promise to do better, to be better, and to make things right between us. I love you and I am truly sorry for not being the best boyfriend.