I was put on "hormone therapy" for prostate cancer, which is chemical castration. The loss of both testosterone and estrogen (yes, men have some) really tanked my libido but lots of foreplay still worked, it just took a long time. Does your wife give you ANY physical affection? Do you cuddle, hold each other, sit against each other while watching TV, etc. Hormonal changes are REALLY difficult as I learned the hard (or not hard 😃) way.

Sometimes there are problems in a relationship because the high libido partner expects physical affection to always lead to sex and the low libido partner doesn't want to give physical affection because they know this. When this has happened to me (as the high libido partner), I learned to just be physically affectionate with no expectation of sex and, surprise surprise, this started leading to more sex. Not always, but often.

Physical affection (not necessarily sex) is really important to most relationships, otherwise you might as well just be friends. Maybe start by something as simple as just holding her hand.