How can I get my girlfriend to break up with me?

I think I can do better. And obviously she also knows this, which is why I fear she will not tolerate a break-up. I got really nice abs and I take care of my body. I am highly educated, whereas she works as a cashier. Also, she has brown eyes, whereas I have blue eyes. It's time to settle down and find the woman who will have my children, so how can I end this dead end relationship without devastating her too much over losing me?