I think what makes the hurt, hurt even more is the expectation we place on the ones we love. "I know I love you and so I'm going treat you this way, speak this way to you, and respect you like this..." and we expect the same thing in return. This is where the shock value comes in. We're not expecting the ones we love, treat well and respect to treat us any other way than how we treat them. So when the time comes and you see the feelings/actions/words aren't reciprocated, we hurt.