I'm going to weigh in as the semi-contrarian here in Cemar-land. Now as I understand it your situation is that your W will have sex with you if you request it but she expresses no desire for sex and exhibits no behaviors that you would interpret as desire during the act. In addition, she has refused to perform certain sexual acts such as giving you head. Am I correct so far?
IMO, the question is to what extent are you looking for validation and to what extent are you simply looking for higher quality sex? When discussing the concept of higher quality sex, I suppose it would be appropriate to use the standard set by Savage and assume that you want your wife to be a lover who is "good", "giving" and "game". So let's examine her refusal to give you head. IMO, that means that she is not "good" in bed because giving head is really part of the standard repertoire of sexual behavior and refusing to do it means that she is pretty lame in bed. One could also argue that she is not "giving" because clearly you really would like to get head and she is not showing a generous spirit in denying you this pleasure. The fact that she is not "game" is obvious based on her refusal to perform an act that could only be defined as kinky by the most sexually repressed members of our society. OTOH, it could be the case that she could/would be a more GGG lover with a man whose behavior was other than yours. Hard to say.
Back to the issue of validation. If your real problem is not that you simply want better sex but that you need a display of desire from your wife in order to feel desirable then that is another matter altogether. Although, based on my own experience, it's really hard to judge your "neediness" in this matter within the context of a SSM. I'm getting tons of validation now from all the men of Match but I still want some high quality sex big time. So, I think that there really is a limit to the whole sexual desire = search for validation of desirability concept. Sometimes you really just want to get laid and you want to get laid by a partner who wants to get laid too because that just makes it so much hotter for the same simple reason that one's day is made a bit more pleasant when the stranger you smile and say "Hello" to in passing smiles and says "Hello" in return. Human beings are social/sexual animals and we are very biochemically receptive and sensitive to how are messages are received and reflected back at us.
"Tell me, what is it you plan to do with your one wild and precious life?" - Mary Oliver