I want to break up with her
Why would you break up with her?
Well it can't go on like this.
It's fine if you want to break up with someone. Not every relationship is perfect.
Yeah, it wasn't. I hurt her a lot last time.
I'm proud of you for owning up to all your faults and letting go of your mistakes. I know it must be really hard, but a great start is needed for the both of you, don't you think? I hope both of you can find better happiness from what you learned together!