I really appreciate this relevant topic, thank you for asking it, Wyatt's Torch!
I'm on a similar spectrum, but on the early edges of it: my husband and I have talked about what we'll do. We don't have a lot of freedom, like most couples, because his job has to take priority at this stage in our lives. So we're both very much aware that my pursuing my doctoral degree will mean separation for the next several years. For us, it helps us to think in terms of practicality: he is well-settled in a career that takes precedence, and, once I get my degree and am settled, he will be at a place where he can then follow my career around, like I've had to for his, until we can both end up doing what we love in the same location.
This WILL be our first big separation, though, in terms of very-lengthy separation. Thus, each of my schools chosen were picked for very specific reasons, one being that I could live with his family, albeit very, very far from our current home. But I'd have his family and that support network, and it would make holidays easier, care of our pets, and the separation in general. I know it won't be a cake-walk, but, in terms of planning for our future, it's a means to an end, and thus worth the risk. But I'm not veteran, and I'm a hopeless optimist. I'd definitely be interested in some more "veteran" people's perspectives of how they manage/matters to consider, when separation is the only recourse. :-)