@romanigypsyeyes haha amazing to know! We don’t currently live together, though, so that’s going to be the biggest adjustment. Hopefully we still like each other when we see each other more than 3-4 times a week 
Oh. Welp in that case, nevermind lol. Ignore my post and carry on, y’all.
Is telecommuting or partial telecommuting a possibility for you?
If it is, it could make a long-distance relationship bearable while giving you time to see what your job options are in the new area – as well as seeing whether her dream job turns out to be a dream or a nightmare…
One young woman I know has made arrangements with her employer to telecommute for a week or two several times a year. She spends those weeks staying with her boyfriend, who lives in another part of the country. And he visits her, too, when he can. But because her employer allows this partial telecommuting and his employer doesn’t, she does most of the traveling. This is not a long-term solution, but it’s something that has worked for them for a few years and may work for a few more. At some point, I think they will figure out a way to live and work in the same city. But for now, they’re managing.
My girlfriend (now wife) was a year behind me in college. We knew each other for several years, but didn’t get romantically involved until the summer after I graduated. That was on the East Coast, and I was headed to the West Coast for law school (a choice I had made some months before in more than a little part because I was sad about not having succeeded in starting a relationship with her). When she graduated, she came out to California with a backpack and a couple leads to completely inappropriate jobs. It was an incredibly brave/stupid thing to do – we hadn’t even been living in the same place during the two months we had dated the summer before – but it made the rest of our lives possible.
Then, I got an offer-you-couldn’t-refuse in Washington D.C. (I had originally been looking in and around Boston, because she had gotten into the Kennedy School, but then she decided not to go there.) She uprooted herself and moved again, not to Washington, but to Philadelphia, so we could at least see each other most weekends. We hadn’t formally agreed to marry at that point, but I saw that move as essentially an engagement – if I wasn’t going to marry her, I would have told her not to do that. Our original plan was to move back to California when I finished my (time-limited) job in Washington, but by that point she had gotten really ensconced in Philadelphia, so we got married and I moved there. It wasn’t a great move for my career, but it was a great move for my life. Ironically, my professional life has been completely tied to Philadelphia since then, while she has barely worked locally in the past 15 years. In fact, for a decade she always had an apartment in some other city where she lived most of the week.
The moral of my story is, if you think the relationship is important, you do what you have to do to make it work. If it works, you won’t regret that. And I hope you won’t regret it even if the relationship doesn’t work.
Note, however, that during the five years we were involved before we got married, we only lived in the same place for about 22 months. We had a lot of time apart to test just how important our relationship was to each of us. And, to be honest, I would not have turned down the DC job if she had asked me to, and she knew better than to ask. If she hadn’t moved back East when I did, we would have tried to make things work really long distance, but I doubt we would have succeeded. We would each have very different lives. That wouldn’t necessarily be a tragedy. You don’t get to live your life as a controlled experiment.
My wife took on the huge burden of being the one whose choice was to follow. I am very grateful to her for that. (And to her parents, for being too distracted by their bitter divorce to stop her. I don’t know what I would have done if one of my kids had pulled something like that at 20.)
OP- of course she will take the job and move. That’s a given. Your relationship will also change because of this. So much good advice already given, as well as examples. Life is full of changes. And compromises. A good discussion is needed.
My experiences. Medical school classmates married each other and had to match residencies together. Compromises in places and specialties needed. I met and married after in practice, job situation changed for me and after I looked at possibilities for his work and mine made a decision. Pros and cons to it but there are always multiple paths that could have been followed with equally good outcomes (none perfect).
You need to figure out priorities. She should NOT give up this job for you. YOU need to decide if you should leave your current one. Your current comfortable life has already changed. There are always bumps in the road in any relationship- even with a long marriage. When those problems occur your wife will wonder if she should have taken that job. You are wondering if she is worth giving up your job now.
I understand wanting stability. But life doesn’t work that way. It constantly changes. We all change- we grow and develop. None of us are the same people we were when twenty, thirty… We adapt to partners or decide it isn’t workable (many on CC are divorced). Your comfort zone no longer exists. I agree that three years is long enough to get to know a person- if you are no longer on the same page this is a good time to separate. Or go for it and relocate. I do not think now is the time for you two to marry as you are ambivalent about things. One of you could feel trapped and become resentful.
I agree that she should not give up the job. However, since you also seem to have a job that you like, I would wait to see if she actually likes the new job and the new city before moving to join her. What if she gets there and hates her new employer or the area and wants to come back? I would wait 6 months, at least, to let her acclimate to the new area before moving. If it seems after three months that the new place is working out, then you can start exploring your options there. By that point, she might have made connections that could help you.
OTOH, if you absolutely refuse to move, ever, I’d do long distance for a few months in case she decides to come back. If she doesn’t, break it off.
" I feel that everything is so perfect now and it saddens me to know that it is going to change. "
If everything really was “perfect”, your girlfriend would not have told you about this job opportunity.
In my opinion, this is her moving forward and asking you to do so with her. If you choose not to, I suspect you’d be answering a question in her mind about you.
It’s not clear to me that she has asked OP to do so with her.