I think, had I had the experience you did, I would have said "I don't want her staying here." If he asked why I would have explained but this is your space and it's his relative.

Sometimes we try to be "nice" when we should just say what we want.

Me 57/H 58
M36 S 2.5yrs R 12/13

Let me give up the need to know why things happen as they do.
I will never know and constant wondering is constant suffering.
Caroline Myss