I was about to ask you a few questions about this, but you've already answered it here... [I'm not going to bring up the boundary issue since others have already mentioned it and you've taken note.]She is extremely pragmatic and practical, and a bit shy in the presence of company. She is either stone-faced and in control, or in tears (pretty rare), and has an easy-going personality. My friends like her, and she does come out with me to some of these events and meetups. She is very intelligent and from a pretty wealthy family (which introduces some complications--I will put that in another post). She is also a few years older than me.
Unlike me, she isn't "moved" by things like art, literature and music.
The dynamic you both share is a different one to most marriages I (and probably, the TAMmers) know of... in some ways, you have a wife that many men dream of - doesn't nag, is very chilled, is very intelligent, doesn't do drama, doesn't demand you curb your social life, doesn't interfere etc...
Then, there's a point when too much of something good starts getting worrying too.
Essentially, in your marriage, you're the fire, she's the ocean... so, while you do passion, she does pragmatism.
I can understand where you come from... and how it can be unsettling overtime if none of your actions ever evoke an impassioned reaction from a spouse... then again, she's always been this way. The bolded portions attest to her personality, and the fact that she's older might contribute to her matured outlook too.
Is she ever protective of her kids/siblings/you? Caring towards you? While you're sick/low, does she naturally show empathy and support? How is she as a mother? Those who have a very detached/cold outlook in life, are sometimes not the best at being intimate, but you say you both enjoy relatively-good intimacy too.
If she is otherwise protective/caring/affectionate but not possessive/jealous, then that is just who she is - a wise matured analytical woman. I'd advise you to embrace that by cherishing this rare personality of hers, and return the respect she shows you in kind by placing the boundaries that she does not demand of you.