Well, im sure she could call the local police station and tell them about whats been happening, request the police to patrol the area from time to time.
make sure she keeps all her blinds shut, windows lockd, and doors etc.
maybe have a girlfriend or somethin come stay with her so shes not alone.
dont answer the door unless she knows who it is and is sure of it etc.
Not much you can really do i dont think, makes it alot harder where your 3 hours away.
Also maybe tell her to leave some lights on and the tv, stuff like that to make the guy think theres more people in there or that someones awake incase he was thinkin about goin in.
Im not a cop but thats all that ive thought up so far.