Dear Kenny1234,
I totally understand your situation now. Since I am a man though. Man always love to being attract. However, I am thinking about one question that a word "Commitment" --> For this commitment, am I willing to give up a chance for the other girls and have the life with my gf?
Another thing that are you a person who feel hard to say "No"? I think you should try to say No to other girl. Otherwise, the situation will keep happen and happen again. No matter how many girl friends you have though. It will be a loop and pain for your life.
"You always have choice" - choose to get rid of this pain or stay in the pain. It's all your choice.