If you are thinking of getting back with an ex girlfriend, its important that you don't rush. This is a big step and you have to take things nice and slow. For starters, think about the reason that you broke up. How was your relationship with her at that time? Probably not too good, I would imagine. So it's important that you don't get back with an ex girlfriend, if its just going to cause the same misery that caused the breakup in the first place. That would just be really stupid wouldn't it?
Instead, think about what drew you to her in the first place? The beginning is almost always the best part. Because it doesn't really seem like work, does it? It's almost always fun and games, because you are still getting to know each other. You always make time to be with each other. Later on, it doesn't feel like that. It feels like you really have to struggle to make this relationship work.
Sit and down and think about the difference between those early stages of your relationship and contrast that to the end of the relationship. Who changed? What changed?
Look at yourself in the mirror! Don't place all the blame on her, irregardless of the reason why the breakup took place. After you have sat down, and really thought this threw, you should have somewhat of a better idea if you would like to get back together with your ex-girlfriend. The important thing is to really dig deep and see if the relationship is even worth saving. If all signs point to yes, then its time to proceed.