Maybe she'd start liking having him around and falling in love with him and she just keeps breaking her stuff just to get him to come around more. Perhaps it's kind of an old rundown house to begin with so they have lots of time to get to know each other (even though with her age, she probably knows how to do a lot of it herself). But then we need to also start thinking, what's the moment when he finds she's a vampire? How does that go, how do they handle it? I expect Elizabeth would be absolutely terrified at that moment, sobbing with fear terrified. 
But then, perhaps she tells him herself. There could be a reason she's do that.  
Would Jaspin start suspecting? What kind of questions would Jaspin ask her about her life? Elizabeth would probably be very vague and avoid answering questions a lot. 

In one night, I think I made my most interesting character of mine in the RP. Not sure how to feel about that.