Is it good enough for you for her to just remain as a "room mate" who shares half of the living expenses?
Is that something you're willing to settle for?
Just remember this isn't all about her, it's about you as well, what do you want? Obviously we have to keep expectations in check but be careful about settling for her staying as a room mate. As the saying goes, "...careful what you wish you for because you just might get it."