ARealLongTime, welcome to the rollercoaster ride. Sorry you are in a situation like many of us here. The good part is you came to the right place.
ARealLongTime asked {{I guess my question is it worth investing more unfulfilled time waiting for her to come around,}} ARealLongTime if you wait it will never happen. My question is what is your life like now if you factor out what you do for or with your W? The reason is, sometimes the H does too little or too much with the W. The key is sometimes our lives get out of balance. Read these next 2 books to see why this might be true in your case.
Please read "Divorce Remedy" and maybe "The Five Love Languages", Gary Chapman.
{{She is reading the SSM book but has already stated it is just another ploy of mine to get her to ML}} My W says the same thing. Her reply is usually that some men and women just write books to convince women to have sex, include trumped up medical clains that having sex is good for your mental or physical health. To my W, sex is why women have mental or physical problems. Of course this is the opposite of what she used to say when her motherhood clock was ticking and she wanteds babies.
Ask your W to name 3 things that might cause her anxiety if you had sex once a week. Do not accept any non concrete answers like I do not feel like doing it" Good answers that you could do something about are what you need. Are either one of you two fixed so there will not be anymore babies?
There was a HDW that told her LDH (no ED problems for H, just no interest in ML) she was either going to have sex with him 2X a week or she was joining a civic organization that met 2X a week. It's called getting a life of your own with out your sopuse.
In my opinion, there are too many so called experts that say a person does not have to do what they do not want to do and the other spouse should respect their wishes, like I am not interested in sex and you have to accept that. To me this is one of the roots of the problem.
There are lots of good people here. Keep reading. Work is calling me.