These are some very valid points. I'm glad that many felt like posting even though the circumstances leading up to the decision to cheat were not laid out clearly.

I think that all avenues should be explored before making a drastic decision such as cheating. One thought I had on the circumstance didn't involve a person who just felt like a change or some irreconcilable difference in the relationship. I was more aiming at a situation in which a partner was happy in their relationship but had lost the inclination toward sex (like those cases we have heard of where everything is fine but a couple hasn't had sex in years and feels no urgency to get back in the saddle).