The NY Times had an article 4 days ago about marriage equality leading to less ML. The most popular comment was that sex is not a necessity in marriage.
On the other hand, not to feel desired or wanted really stinks. Without that I don't see how a M can work. I absolutely sympathize with what happens to your self-esteem and confidence, and am sorry to hear it. It feels like the taproot of our self-esteem has been pulled out.
If there are any fun meetups near you, perhaps just getting out of the house and away from your W could buoy you up a bit. I have the "luck" to spend lots of time away from home, and go to meetups there, and have fun. Just feeling the vibe from other women there has helped.
Luke
M58, xW54 S22, D18 M 1984, D 2016 Living a new life.