People are naturally attracted to differences. If your wife was blonde i bet you notice your attracted to brunettes or redheads when you previously were not. I swear as men we are wired to be either really disciplined or to cave to our urges. What makes it worse is the women ive been around ive noticed are more drawn apt to flirt or respond to a seemingly "taken" man. Either because they percieve us a desirable , or safer, or maybe because we act alot more mature when we arent a walking hard cock like most of us are when we are single. My advice to you is to make whats old new again, talk to your woman and educate yourself and her sexually. Find out about each others fantasies, and do new stuff sexually. Its cheaper to keep her