I'm assuming this is aimed at the male side of the forum, but i'm going to add my 2 cents worth anyway ....
When you have an urge to cheat, regardless of whether its because you're drunk, or the women at work are "wow", there is something wrong with your current relationship ....
Life is way too short to be dating someone who is not making the relationship a whole ... rather carry on trying until you find the right person, and if you decide this woman you're dating is the one for you, you should not be having any urges whatsoever to be cheating ... to be frank, either the relationship is broken, or the person wanting to cheat is simply not worth being with at all. Rather just break up with the other half before doing anything.