Almost my first husband and I sound very much like you and your wife. No role reversal - I was the one who had no sex drive in part caused by a specific sexual issue between me and my exH which we did not have sufficient intimacy and maturity to discuss and resolve.
The one slight difference is that he never really attempted to
discuss the situation. To be fair, he did try very early on in the relationship/marriage but not much changed and over the years we just stopped talking about it. It resurfaced when we were in our late twenties and started to see our friends starting families etc. At that point I did try to talk about it a bit - "was he concerned about our lack of sex life" and his response - "not really, it seems normal, we work hard etc". The truth was by that point, after living like brother and sister for so long, his sexual feelings for me were stone dead and there was no reviving them.
He had an affair. It had not gone too far when I found out and we separated. He is now married to OW, I assume happily.
I wish the relationship had not ended in an affair, I wish we had instead had the maturity and courage to discuss our issues and conclude that our marriage was over. BUT we had become so unable to be intimate in any way by that point I don't really see how anything less "catastrophic" would have moved us out of our rut.
I'm so happy now. I sometimes feel like I don't deserve it (not in any serious, needing counselling way) but I think I did make my exH very unhappy (he contributed to his own unhappiness too though) throughout our twenties and effectively made him the scapegoat for the end of our marriage. I learned so much from that relationship that I have brought into my second marriage and in some ways I'm glad that something/anything happened, even the affair to set us both free. Be sure, I'm not recommending that to you as a course of action but do you think your wife is really happy?