Thanks, Hairdog, for the asexuality link. What I'm finding is that the academic literature is sometimes (often) at variance with the self-help literature or the online community information. First of all, people who read books like Passionate Marriage or SSM are usually better educated and more proactive than the general population. At any rate, I have become convinced that there are some people who for all intents and purposes are asexual (and anthropologists writing on this subject are beginning to include "asexual" alongside, hetero, homo and bi- categories. I can remember a time, btw, when the mainstream research insisted there were NO bisexual people - and a lot of us went to college in that era. I am glad to hear that your wife thinks she has a sex drive. It would of course be a stretch for her to actually look into the literature on sexuality, physiology, etc. But her neck-nuzzling behavior interests me. Research on pheromones is controversial, but there is a Harvard biologist (female, her name escapes me) who believes that without someone in the relationship producing testosterone-related pheromones/biochemistry, there isn't going to be a lot of active sex-seeking behavior. That's her explanation for the small amount of sex reported in several lesbian couple studies. Of course, females can produce those pheromones as well, and it looks like women need very little T to get their engines running. Perhaps your wife is discovering that, on her own.
I have just ordered PM and will read with interest. I'm teaching the gender and sexuality course in the fall and right now, my syllabus outline focuses almost entirely on physiological states and sexuality - there's just so much in that one arena and frankly, it doesn't get taught very often. For example, in research menopause, I learned that unless women fantasize erotically at least three times a week, their levels of testosterone drop to near zero. So it becomes a mind thing, to get your body to produce any sex hormones at all (remembering that most women have lost nearly all their progesterone and estrogen at menopause - although not entirely the case for every woman). Women who actually have satisfying sex once a week and fantasize about it more often than that remain much more sexual than those who don't. Someone should be researching the effects of these hormones on such things as vaginal dryness, various arousal responses, etc. (It's always been said it's all estrogen, it may not be so straightforward - and wouldn't you know it, the research is VERY sketchy). Male sexual health and viagra related research is rampant.
I'm sure some research is being done somewhere, I just use the basic resources like medline and Jama and the Journal of Obstetrics and Gynecology to try and keep up, but I'm still in shock over the lack of research into the physiology of the female sexual response.