Although I was often told how "lucky" I was to have a non-academic partner (a subject for another time,) I struggled mightily with how and when to incorporate my non-academic partner into my graduate school life. My partner is a software engineer who worked a variety of jobs during my PhD process. He is a smart man with a graduate degree of his own, but some of our biggest relationship challenges came from his desire to live a life together that was not completely ruled by my graduate student schedule (and mood.) I would not claim that we did this perfectly, but after five years, we settled into a workable pattern based around these ideas.
Have scheduled time that is work free. At times, my husband's schedule was just as crazy as mine, but we made it a priority to eat dinner together. Sometimes he cooked, sometimes I did, sometimes we ate frozen vegetables with scrambled eggs, but we both knew that even if we didn't see each other the rest of the day, we had about an hour set aside to reconnect without our phones and laptops and books.
Decide on a policy for reading work. Although I know several couples that are great editors and readers of each other's work, I made the conscious choice to not have my partner read my academic work. There was the obvious lack of overlap in our trainings (I have had way more Foucault and way less Python) but this helped to keep our relationship "clean" for me. My confidence as a writer ebbed and flowed, but mostly ebbed, and it was a comfort that he never saw my writing at its worst, most unpolished. He was never waiting on drafts, and I was never waiting on his feedback, and we never had to fight about whether or not he was qualified to critique my use of theory in that paragraph. As I do not review his diffs or give feedback on his slide decks, this made it so that we were both the experts in our respective domains. But, this did have its consequences. My partner will be the first to tell you that he often felt disconnected from this part of my life, and that not knowing my work made it difficult to make small talk at academic parties. No solution is perfect, but that was ours.
Respect their distance from the "bubble." Honestly, this was the hardest lesson for me to learn personally. Because my partner was outside of the department, I initially did quite a bit of "venting" to him, because he would have to take my side in the tiffs, big and small, that arise in closed, competitive circuits like academic departments. But, as the years wore on, I stopped sharing as much about the day to day dramas that unfolded for me professionally. While this was, I'm sure, a relief for him to not be updated every day on a soap-opera that he doesn't even watch, it eventually became a relief for me as well. I realized that in rehashing all the minute details from this microenvironment, I wasn't processing them as much as I was reliving them, prolonging the negative feelings and making situations more intense than they needed to be. When I wasn't constantly replaying these dramas, their power over my emotional state was lessened.
Honor your commitments (as far as it is possible). My partner and I have "google calendar intimacy," in which we can see each other's calendars and send invitations to events we would like the other one to attend (family parties, concerts, forced cleaning of the house, etc.) If I said yes to something, I tried my very best to honor that commitment, no matter what kind of day I was having, or how much progress I had made that day. The big shift that made this possible was not thinking of time off, or non-academic activities, as rewards. It isn't a reward to go to dinner with my in-laws, it is a commitment on the same order as a talk I'm expected to attend or my office hours. I would have never dreamed of rescheduling a meeting with my chair because I was behind on my grading, and so I had to extend that same courtesy to events and activities I committed to in my personal life. Deadlines come and go, but knowing that you can be trusted to show up when you say you will helps feed your relationship long after the chapter or manuscript is turned in.
I am not a perfect partner, and I especially was not during my PhD. But, my life was always bigger than my dissertation, and just as other professionals are encouraged to have lives outside of work, these guidelines helped me do the same.