I'm keeping that in mind as I head into this. I have a tiny studio apartment, so privacy and time alone would ordinarily be thin on the ground right about now, except:
hcolleen works mornings. She wakes up ungodly early (I have run into her on IM some nights before I fall asleep) and leaves for work also early. By the time she gets home, I am at work. She goes to bed early, and sleeps like a rock. (Her yaoi buddies in NY tested this.)
I work evenings. I wake up around 10 to 11 on most days, get to work at noon, and work until well after her bedtime. I go to sleep around the same time she is attaining consciousness.
I wound up only seeing Sis once or twice a week on that schedule, which was actually not enough. Since this is a studio, that may well counteract the antisocial schedule problem.
The primary consideration, however, is our interaction under stress. I have been in her presence with all defenses down and not felt threatened. I cannot do that with most people, not even friends. That says a whole lot right now about how things are likely to work out. If I do not feel threatened, I do not snap. That is a good thing...