@dagmaraka,
My thinking exactly, dag. You beat me too it.
As the young one sounds like rather a nice person, surely if you explained
your predicament to her she'd get it? Seems to me that she's only seeing things from her side at the moment. And it sounds like you have no time to lose!
Besides, as the person with the ongoing commitment to the house, I think it would be perfectly reasonable for you to (very nicely, of course!) "pull rank" in this situation. You simply
can't afford to carry the entire cost of the house rental if a suitable person ( you both agree on) can't be found. And It is not as if you'd decide on any "old" monster!
Is that Irish folk singer still looking for a place to live?