I moved 500 miles from VA to PA to be with a guy I met online (not a dating site, it was another message board). We were back and forth many times and I finally moved there a little over a year after we met. He has PTSD and is very mentally unwell at times. I moved back after 5 months, which was 2 years ago the beginning of May. We are still close friends.
I’m not sure if I qualify since I fully intended to return to Thailand anyway. But becoming involved with my future Thai wife at grad school at the University of Hawaii definitely sealed the deal. We graduated together and then headed for Bangkok. (I’d already previously lived for a couple of years in northern Thailand.)
The future wife had to return out of obligation, because she was already a civil servant, and her office had sent her to UH to pick up a second master’s degree, in biostatistics, for use in her career. Spending 2-1/2 years at school entailed a further five-year commitment in the job, or else her family would have lost a lot of land that they’d put up as a guarantee. That was literally decades ago, and we’re still happily married in Bangkok, and she’s still on the job too. So it’s worked out quite well.
I should add that while it’s true I fully intended to return to Thailand anyway, it was by no means definite, as I could easily have stayed in Hawaii. Wonderful place. Even today, we often kick around the notion of retiring back there some day too. So maybe I qualify for the question.
On the other side of the equation, my wife and I met in Houston and lived together there for 18 months, at which point she agreed to move to Salt Lake City with me in order to be near my kids from my first marriage. (She is widowed, and has one child who lives with us and calls me Dad.)
Her parents live here, and she went to high school here, so it isn’t complete terra incognita to her, but she doesn’t especially like it here, and I’m sure she would never have moved back to Utah if not for me. I consider it a major sacrifice that she made for the sake of our relationship, and once we’re able to leave here (e.g. ex moves somewhere, last kid graduates high school), I will cheerfully go wherever she wants. Back to Texas? Sure. East Coast, where I grew up and she has lived? You bet. Pacific Northwest? Absolutely, dear. 
But not Ohio. If there’s one thing I’ve learned from this thread, it’s that you can only be forced to leave Ohio for love; never to go there. 
In 2003 I was living in my parent’s house, working for a temp agency and pretty much at loose ends. I met this guy online (at the wretched hive of scum, villainy and twink shallowness that is gay.com, no less) and we started chatting. In the course of about 3 months, I decided to uproot and move to Lancaster to be with him. 11 years later, I’m still here and we recently got married (pretty much the same week such became legal in this state).
Wait…not Lancaster, Ohio, right? That would break the thread.
No, Lancaster, PA.
I’m from near Lancaster. That would be weird. 
Anyway, Asimovian may decide some day that he really wants to own a big house in the suburbs. We’d probably end up in Ohio for that, since a big house in the suburbs in LA is… not likely.
“Ever move for big property lust?” is a different thread, lady.
I meet most girls in real life, and if I were to do so online I make it clear that I am in L.A and not willing to move nor should she move for me. No matter what.