Mana4989

I think people are projecting it as a binary choice because labs often require its students to be physically present and because universities often expect some sort of service in exchange for funding which can't be done remotely.
 
I think this is easier to say now but nearly impossible to say what you will believe in a few years time. While you might not blame him, you might regret not knowing what would have happened if you had continued or you might be relieved that you're no longer having to do additional lab work.

I don't why most people are projecting it as a binary choice -- to complete it or to give it up. Have you considered the possibility of a middle ground?
A colleague of mine was an international Ph.D. student in the US, got married in between, partner couldn't travel because of visa issues, so the colleague wrapped up their course requirements and moved to their home country to live with their partner. They found a nice job back home -- the work aligned with the broad theme of their Ph.D., and they continued to work on their thesis, interfacing with their advisor and their lab through skype, etc. They were still enrolled in the Ph.D. program, but their advisor was no longer funding them so they had more freedom and continued to work at their pace. Of course, their Ph.D. was in computing, so it was possible to work remotely as you don't need any fancy lab equipments or apparatus for your work. 

Based on what you have described in your post, you might be able to work out something similar. Instead of spending all of the next 3-4 years, you can also break it down into chunks -- spend the next year or so gearing towards your goal, and becoming more independent, so that you can easily move to your home, and then work remotely from there. And since your partner already has a job in the home country, I believe that is not your major concern, and you could also just focus on completing your Ph.D. while also being by their side. 
 

The PhD will end at some point soon, however, your partner will always be there...if you're meant to be together. I say complete your PhD and then go back to your country. It's tough now to transition from being together to being alone in the US, but remember, it will come to an end, no situation is permanent. Also, in my thinking, if your situation was reversed and you were done with your post-doc, would you be okay with letting your SO quit their PhD program just because you finished yours ahead and want to move back home? Don't quit, you just have to work harder at your relationship in the time you'll be apart. 

How close are you to finishing? I know there's no guarantees for how long a dissertation may take. It sounds like you've put a lot of hard work into this PhD already. Will you be ok with just walking away from that? Do you feel you may resent your partner in the future because you gave up your dream for him?