Judgments usually stick because they are only looked at from one angle.  You judge people through the lens by which you judge yourself or through the story that fits your narrative of that person.  By looking at your partner as a mirror instead of a dead end, you can continue to grow and develop more parts of yourself that you are unable to see without their reflection.  Many different processes use this same concept that I've dubbed "The Mirror".  If you are holding onto any resentments or judgments of your partner, this is the perfect exercise for you to learn.