Oh Luckygirl - that sounds like an awful situation. I'd find it very difficult to have someone like that living in my home. It's weird.
In truth, I suppose she is doing what is required but it might be nice if she put the kettle on occasionally and had brief chats with you too. I hope your OH isn't bothered by her lack of social skills.
The agency has to vet (and train!) their staff more carefully. £800 a week is a fortune, given the interaction is limited and it's also creating a difficult atmosphere at home. I would feel very uncomfortable. (She behaves like a vampire!)
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