I actually lived in this kind of situation for a while, where i was the person sleeping in the extra bedroom. Difference being it was a house, and the owner was a little crazy - like he would yell at me one day for not being social enough when he had a guy friend over, and then tell me i was hovering too much when he had a female friend stay. And then he had a drinking on lithium problem and i just was not educated enough about these issues, or i was in denial myself. I mean, it was back before everybody had cell phones, so even the phone was an issue! Thats so funny now!

You might want to have coffee together in the morning, or breakfast once a week, or some set time to talk about issues that might arise. But it sounds like you are already being a more than gracious hostess. As crazy as he was, i did enjoy my time with roommate. But i think he travelled a lot and i was more like a housesitter.