Why the breakup? Try to think about why you've had a breakup.
Don't focus on who's "fault" it was, just think about the reasons or motivations for why it happened.
Think about why you and your former lover were together in the first place.
What was it that kept you together until the breakup? Sometimes what draws a couple apart is lack of communication.
A guy stops telling a girl he loves her.
He stops listening to her.
He stops encouraging her and reinforcing her.
Can you relate to any of this? Are you encouraging? Discouraging people are hard to be around.
It may be that over time your girlfriend felt that you were not very encouraging and positive about the relationship, and about life with her.
She may have felt that you didn't care as much because you didn't seem to be listening to her.
It's easier to diagnose if you know for sure or have a pretty good idea of why the breakup happened.
If for example she said that she didn't feel that you loved her, then in order to get her back you are going to have to show her that you love her.
Don't just say the words, but show her! How to show her.
She needs to hear that you love her, that you are proud of her, and that you are willing to listen to her.
However, at this point it's hard to say these things because the relationship is broken.
One tactic that will go a long way toward reconciliation is writing her a letter.
Write a letter accepting the breakup and recognizing where you've fallen short.
You're not asking to get back together, you are just being humble and admitting to your mistakes.
Don't try to beg to get her back!