Febrifuge, a lot of what you're describing sounds like what happens when we get together with people while we're still relatively unclear about ourselves and who we are, and when they are in a "growing place". A lot of it sounds like, in your case, what she wanted *at the time* turned out not to be what she wanted *later*.
I think one thing is that new career directions reflect new directions, and deeper changes within us.
Situation with my own partner is that I got together with him as a relatively "unformed" person. We were socially at the same place when we got together - a couple of geeks, misfits, outcasts who only fit in the little geek/misfit/outcast social sphere we were part of. I really thought he and I could do the hippie/geek/bohemian thing the rest of our lives, when we got together; I had no idea how much I would change, and neither did he.
I was deeply unhappy when we got together, and I was just thrilled that somebody came along to love me. I was open to whatever he wanted, because I didn't know what *I* wanted.
Things started to change after I started getting treated for depression, and started finding out that I was a PERSON under the depression. More, I found out that I wasn't even the person I thought I was; as I explored myself in therapy, and got new confidence in school, my old passion for science came back. Suddenly I had interests other than video games, manga, and AD&D. Suddenly I was into physical activity. Suddenly I didn't fit with my old friends of fifteen years - and that meant my husband, too.
When we got together, I didn't have a job. I moved 600 mi. to be with him because after all, I was "open" to everything. I didn't know if I wanted children, I was "open" about a lot of things because I didn't know how important they really were to me. The longer we were together, the more I discovered what my real feelings about things were. I didn't think my Jewish background was an issue since I didn't identify as religious, but when we fought over the Christmas tree thing *every* time, and over how to raise our kids, I realized that it was more important to me than I thought it was.
I realized also that I didn't want children (at least not with him - he's very childlike himself), that I wanted to go back to school and pursue a career. A *professional* career, not just get a bachelor's degree then just get "any old job" which is what he expected. He was figuring that I would finish school in another two or three years, then he could go back to school. Then at some point, we'd start a family.
I "went along" with him about a lot of things when we got together, because I didn't yet know where I stood. He is totally opposed to TV. Now we have a TV (I brought mine with me), but we fought over it, and he'll *never* get cable. He also has an issue with cars, especially the type of car I want to drive (something large and trucklike, that can move stuff). He has issues with any of my more "professional" type of friends. And I discovered that I'm not really into the science fiction fandom world anymore, not the way he is (though I still read s/f, and comics, from time to time). I'm as uncomfortable in his social groups as he is in my Toastmasters meetings.
It would sound really ridiculous when I say that a lot of why I want to leave is... I want cable TV and all the normal things every other boring person wants. I like throwing a ball around in a park, and hiking through canyons with a dog, not just sitting in a basement at 2am playing AD&D. [I am still friends with some of these people - but I usually come to visit them and leave before their gaming starts, or sometimes I bring my math books and sit in the corner working on my math, then visit with them when they take breaks from the gaming.]
And I want to be able to move in a wider variety of social circles. I have hippie bohemian friends too, but it's not the *only* place I fit.
This sounds a lot like two people who got married in their twenties, then split up in their thirties, but believe it or not, we have only been together two years (married one year). A lot has changed in those two years.
I know it sounds like I'm deciding to "trade up", but it makes me wonder, when people "trade up", if there are really deeper issues going on than it appears to other people.