I know it is scary for you, Fred. But I see opportunity here. You have a choice as to how your use this experience. You can use your new experience as a way to empathize better with what your wife may have been feeling. Or you can use it to punish your wife with "see what it feels like!" Which approach do you think will be better for your marriage? Does the idea of nurturing empathy for your wife make you feel good or do you feel hostile to the idea? If you're feeling hostile to the idea of nurturing empathy, what do you think about that?
I'm with LL wholeheartedly. Tell your wife you don't get what is happening and it is horrible feeling this way. Then maybe say something like, "I think maybe I understand a little better what it may be like for you. You must feel pretty bad too when you haven't wanted to have sex with me." Then pull out SSM and go to the first chapter near the end and say, "Let's be like those couples that are working together on improving our sex life." (Okay, that last part may be a little stilted and too contrived.) But my point is to encourage you to use and do whatever you can to nurture your own empathy and positive feelings for your spouse, to encourage a joint approach to solving the problem.
Your wife has indicated a willingness to work harder on this. Don't forget to let her know you appreciate that. Do what you can to create an environment which keeps that going. Empathy promotes a sense of intimacy and love and mutual care.
Maybe your wife will be able to use the experience to empathize more with you. I hope she does. You don't have any control over what she chooses to do with it, however, so don't dwell on her choices. Keep your eyes on what choices you're making.
Also, as someone who has experienced a loss of desire, don't stress over it. Treat it as a temporary thing. Remind yourself that sometimes you need to just go ahead and the desire will kick in. Don't dwell on your initial lack of response...it will make it worse. Replace thoughts about your lack of response with memories of times when it was great.
