It doesn't matter what his reasons are. Men do not have a right or an entitlement to sex. Sex is what happens when two people come together because they both want it. If one doesn't want it then it is rape. If he couldn't make it enticing enough to get his wife interested that is his failure, not hers. The moment you start keeping a ****ing diary of your wife saying no you've entered the realm of ****ing creepy, misogynist entitlement for which there is no excuse.