>>And mind you, he barely initiates sex with me anymore so how could he please ANOTHER woman when he rarely has sex with me???

This is obvious: He gets off on novelty. Now that you have been with him awhlie, you are no longer sexually novel. Another woman would be novel, so he'd fck her like mad (sorry) and possibly bring that energy to you as well, but it isn't a given. Until he got tired of her, too.