I wouldn't end a friendship over something like this, but I would reevaluate how close we were.
But the thing that sticks out for me, maybe because I have a similar problem, is the anxiety about hosting people. I get that part of this is due to a problem with your medicine. But part of this is always there for you, right? Feeling that you have to host people if they are in your home and that bringing on anxiety. So you should be careful about giving people blanket invitations to stay at your place. I say this because while I've gotten much better about my issues with hosting people, I know what my limits are and I don't make promises beyond them. I think once you stabilize your meds, you should reevaluate things for yourself. Maybe you and your fiance need to stop making that offer and field any requests that you get as they come.
As far as offering a "night", some emergencies, even blizzards, cause problems for more than one night. That should be taken into account as well.