I agree with the others.
My wife's boyfriend is 2 inches longer than me. I don't let that interfere with the relationship me and Jess have. She loves sex with both of us. There are qualities of him that she loves and then there are qualities she loves about me. It's just different, that's all. As long as she loves you and treats you as a partner then you'll be fine. Try not to get so hung up on dick size.
Do what you are.