Re-read guys... I did say there is still no reason to cheat... however, not fulfilling your man (or in a man's case, his woman's needs) sets the stage for them to do so... it may not even be the partner's original intent but it winds up turning into cheating.... the book gave examples and I'll paraphrase to demonstrate the theory....
1) man cheats on woman:
Man has a strong desire to go to sporting events, would love his lifepartner, his wife, to join him. Wife hates sports, wife refuses to come. Urges husband to go to sporting events without her. Husband goes. Single woman who loves sports befriends him. Single woman and husband begin to bond on strictly friendly basis. Because wife is not doing what single woman will, husband starts to look forward to time spent with single woman at sporting events and bond begins to strengthen beyond sports, into friendship, into fondness, into caring....on and on and on... eventually cheating. When his desire intially was to share this experience with his wife.
2) woman cheats on man:
Husband loves wife and wife husband. Husband has been taught that to be a good husband/father, he is to be a provider. Husband works like a Hebrew slave. Doesn't spend time with his wife and family, but believes since he's providing financially, he's doing "his part". Husband isn't affectionate with wife. Wife feels lonely and abandoned. Co-worker, just friendly guy, is known for draping his arm around people as he talks to them, men and women alike. One day, coworker drapes arm around wife, giving her a squeeze. Wife feels wonderful. Keeps looking forward to this man's touch... and begins developing feelings whcih eventually lead to cheating... if husband were to meet her needs intially, there wouldn't have been that problem.
The book doesn't say cheating is right. It's not ever right. But the cheater is OFT times pushed in the direction of cheating, if their partner isn't meeting their needs.
HTH.