I live in whitley bay, have done for a year now. Its definitely on the up, although the south end, next to cullercoats is probably best avoided. Tynemouth rents are very high. Whitley bay not so much so, but both areas are mainly families.
I lived in Jesmond and heaton in Newcastle for years, both have become overrun with students,and jesmond rents and house prices are daft. If she wwants to live in newcastle look at south gosforth and Ilford road IMO
Theres an area of North shields, next to the park that seperates tynemouth and north shields which is lovely. big victorian houses and flats, and prices are good, but rising pretty sharply, renting here could be a good option.