I'm starting to wonder what you were hoping to hear from Mumsnet posters, OP?
Did you, as someone suggested earlier, want permission to go ahead and find an FWB, affair or sex worker?
Whether or not that has the case, if the situation is exactly as you describe it, no-one on this thread can help your DW regain a libido, or help you come to terms with not having a sexual relationship in marriage.
Posters have been thoughtful and generous throughout this thread with suggestions, some for you and some for your wife. A lot of these ideas seem to be shut down right away in your replies.
That said, even to explore any of the ideas suggested depends on you talking to each other openly and honestly (with or without the help of a relationship or psychosexual counsellor).
You've not indicated as far as I can see whether you and your DW are communicating currently and in depth about this whole subject.
If not, why not?
Does she know about your post? Would you tell her so she can see the responses people are offering? I wonder, would she agree with your take on the whole situation as per your posts? Would she be able to decipher what you were hoping to get from responders?