say "having you here for too long will probably stress me out" without it sounding bad, like he is just a source of stress instead of our friend (when in reality it's not personal, having *anyone* here or really any major change to my environment would be disruptive - I am also still coping with stress about how the storm is going to affect my school and work obligations, not to mention my overall concern for all those still affected who we are trying to help by volunteering
This is what the OP said. That having the guest would probably stress her out. It seems as though we are characterizing her situation as crippling, when that is not how she herself described it.
As for the stress of concern for others mentioned in the OP, this favor might be one way of feeling like she is able to so something.
She's already stressed. From LadyL's first post:
What made the situation hard was right before the storm I had a medical situation come to a head - I started having a negative reaction to my migraine medication - sleep disturbances, some weird perceptual effects, and severe anxiety (these are all known but not super common side effects of the med I take). I have been in the process of slowly and safely tapering off the meds but in the mean time, my anxiety levels have been unpredictable and disruptive. I am normally a bit on the anxious side, but between the meds and the storm related stress it has amped it up to where there are times I can barely function,