I'm going to break up with my girlfriend.
Why do you want to break up with her?
I feel she has changed so much recently, she was different when I first met her.
You don't have to stay in a relationship if you feel your partner has changed so much that you're no longer good together. Make sure to communicate clearly with your partner about the breakup. This will help to minimize the hurt of ending the relationship.
Yeah that sounds nice, she has changed so much but I don't want to hurt  her.
It is sad to end relationships but sometimes we grow apart and it is okay to end them. It is better for you both to be with people that are better for you.