Would you break up with your girlfriend if you asked her a question and she responded like this...?

So i took my girlfriend on a date and it just didn't feel right so when we got back to her place I asked her if she thought of me as a friend or a boyfriend (we have been dating for 18 months) she said that she didn't know and then after me telling her how great I was she decided to keep going out with me. Does this mean she is over me and doesn't want to admit it or am I digging to much into it. Do I break up with her or not.Would you break up with your girlfriend if you asked her a question and she responded like this...?
hmmm... This could mean a few things. Maybe she's fallen out of love with you ( I hope not) maybe she misses who you used to be. Maybe you two need to spice up your relationship..... I don't know. Good luck