I pulled this down from another website. A good read overall. But this was my favorite excerpt on what a cheater is.
Irrelevant of the excuses and justifications, everybody knows it's wrong, everybody knows it ends their relationship right at that moment, caught or not. Every cheater would go ballistic if they found out they got cheated on.
People cheat because their emotionally immature. Simple.
I'd dump you're worthless ass in a nano second. Because it shows me you're incapeable of even knowing what a committed intimate relationship is, let alone you've got no strength, integrity, empathy or intelligence.
Oh and let me add, i've had a lot of experience, and emotionally immature cheaters always have a higher opinion of their worth and sexual prowess than is justified.
You're betraying, lying, selfish, manipulative personity is apparent in every part of you're life, not just you're sex life.