I should say that her drama isn't the only reason I need to end this. Our schedules mean we don't get to see each other much, and it's wearing thin for me. I don't get the "real life" stuff with him (cleaning house, running errands, etc.), so I am pretty much a single woman in all those respects. It's another "fairness" aspect for me: they do all the mundane, "couple" stuff at their house, and I have to do it all alone. While they each have a helpmate to accomplish tasks, and get to spend time together doing them, I support my household (bills, chores, errands, etc.) completely independently and completely on my own time (because having him help me do it would mean giving up the very little time we're getting to do anything other than go to bed). They don't understand why this makes me feel secondary, btw.
Since I have a full-time job on a different schedule (that I can't change), I spend a lot of time physically exhausted because unless I stay up way later than I should to spend time with him, I don't see him for more than a few minutes a couple of times a week before bed, and then a full day or two every two weeks. I am staying up those extra hours, which is leaving me beyond tired (and he's getting up early, which is leaving him tired). When I am single, being alone is fine. I like my alone time. But, when I am in love with someone, this little time gets to be a problem. Especially when it's a very limited window, because it often means giving up doing other things I would like to or should get done if they happen to fall on those tightly-schedule days.
The short version is that it's not working, and it's not likely to change. I get that. I just don't want to.