There has been a lot of research lately on the biology of sexual desire and how it relates to infidelity. There is evidence now that women have a biological trigger for infidelity. So when your wife loses all sexual interest in you, and then recovers her interest with another man, it might have nothing at all to do with how supportive or sensitive you were in the relationship. She might have just had her infidelity gene triggered. And since society does not allow her to cheat, she had to divorce first.
Some interesting reading for the scientifically inclined: "Promiscuity: An Evolutionary History of Sperm Competition" by T.R. Birkhead "Myth of Monogamy: Fidelity and Infidelity in Animals and People" by Barash and Lipton "Anatomy of Love: A Natural History of Mating, Marriage, and Why We Stray" by Helen Fisher
So quit beating yourself up, the answer to most of our questions about the mystery of female behavior can be found in the human genome. Yes, you should continue to work on your relationship, and emotions are a critical dimension to sexual behavior. But it's no surprise. Sex is about reproduction, so genetics plays a very big role.
