how can i get the attention of a girl that i find beautiful
Be kind and gentle and sweet to her, don't do overly stupid things to impress her, by don't just sit and stare either. Ask her friends what she likes, then try to make her happy using them without being overly suspicious. It's all in the approach.
Really.. This is why your breaking up with your gf.. Cause you think someone else is attractive.
Talk to her