It is my understanding that you have told her that you have no intention of marrying her. Is that correct?
If not, then you need to stop leading her on.
It seems to me, that she is working for the commitment. Once she has it, then her actions will fall back to minimal effort. It will NOT get better.
Again, if you are leading her on, that isn't the right thing to do. She deserves to know your intentions. You deserve to know hers.
If you want to marry her and are unsure as to the level of her commitment, then a pre-nuptual is in order to protect yourself financially.
I still think you should just end it.
All the best, -NOPkins-
I will ferret out an affair at any opportunity.
-An affair is the embodiment of entitlement, fueled by resentment and lack of respect. -An infidel will remain unreachable so long as their sense of entitlement exceeds their ability to reason.