When someone feels no remorse over cheating on their partner, it only means they never cared for them in the first place. Think about the world of hurt that revelations of infidelity can put the victim in. It's like taking a knife and stabbing the person right in the heart. Studies have shown that emotional pain can be just as damaging -- if not more so -- than physical pain. And when one experiences this form of betrayal, it can feel as though their world has come crashing down. Imagine investing your time, effort, and emotions in someone who chose to throw it all away in an act (or several) of pure selfishness. The least they could do is fess up and allow their partner to find someone who will actually value their loyalty. Unfortunately, it's very hard to discern early into the relationship whether your partner is prone to cheating, or will slip at some point. (It isn't as if you're going to put out feelers by asking his friends or relatives whether he...