... the reason people cheat is because of character defects and lack of boundaries. A healthy person doesn't need some strange woman to feel good and get attention from. A healthy person in a relationship doesn't let it get to the point that some strange woman gives him attention, because he has boundaries in place to protect his relationship. If his relationship gets rocky, he pays attention to the relationship in order to fix it, or he decides it's not fixable and he leaves.
I totally agree; I would never even START down a path of intimacy or closeness with anyone other than my BF. But I also agree that a person could cheat because they want to feel wanted. Someone recently asked me, "How do you KNOW you will not cheat?" My response: "Because I am just not that desperate that I would need to do that in order to feel good about myself." In other words, I have matured enough that I don't need another person to validate me.