As a man, I find cheating on someone to be the most dishonorable thing one can do. And a man is nothing but a waste of air if he has no honor. If a man isn't happy being with a woman, he needs to talk to her about it and then they both need to move on. Don't lie and break her trust. As they say "man-up" and do the right thing.

Don't worry about whether he finds you attractive or not. Kick him to the curb, there are plenty of real men out there that will treat you the way you deserve.