In this counseling answer:
• Make istikhara on the matter and allow Allah to guide you.
• Ask yourself if the way you are feeling is simply a result of having had this relationship with her.
Assalamu alaikum wa rahmatulahi wa barakatuh brother,
May Allah guide her and all other non-Muslims to the path of Islam. There is no harm in making duaas like this for her and other non-Muslims. You can continue to do this for her regardless of whether this ends in a marriage between you or not.
To help matters and avoid prolonged haram contact between you, you could direct her to some of the online organizations that offer a course in Islamic studies so she can learn about it herself, especially since it seems that she is quite curious, and in sha Allah see the light of Islam.
Of course, while you are not married, she is haram to you so you need to be careful about any contact with her. If you wish to pursue marriage to her, make sure to do so in the correct way.
Make istikhara on the matter and allow Allah to guide you both to marriage if this is what is good for you both. If it is not, then he will separate your ways and your hearts.
When considering whether this woman is the one for you, bear in mind how the relationship started. Almost inevitably when a man and woman spend intimate time together, they will develop feelings for one another. So, ask yourself if the way you are feeling is simply a result of having had this relationship with her. This can lead to confusion about whether you truly love her, or whether you can attain the same feelings with someone else in a way that was developed via more correct means.
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If all this is because you are at the stage in your life where you would like to marry, then there is no harm in you seeking marriage elsewhere. You are not obliged to this present woman.
Understandably, given your history, you donate feelings for her which will make it difficult to look elsewhere, but keep in mind how those feelings developed in the first place that may be tainting your view of where to go from here and restricting you from seeking other options.
If you still choose to meet her, make sure to have someone else with you at least so you are not alone together. This will also allow for the presence of someone who is neutral and impartial in the matter and better able to advise you on whether taking things further with this woman is a good idea or not.
May Allah guide you both and grant you happiness and contentment in this life and the next.
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