What is going through my ex's head?

To make a long story short me and my ex broke up on wednesday. She is now with another guy that wants her to move in with her and she cant decide whether or not to do it. Well on Friday I went over to her house and one thing led to another and eventually we had our hands down each others pants and were making out. We were about to do something when she said she wanted to but couldnt. We had a very sexual relationship prior to the break up. After we made out a few more times I ended up leaving as we felt bad after it happened but we both wanted it. I still love her and right before I left the words I love you slipped out her mouth but she said she didnt mean to say it. Later she texted me about the day and said she didnt know about anything. We havent talked since then and im still trying to figure out whats gong on in her head. I know she loves me but she said she doesnt want to hurt me. Any advice on whats going through her head will be useful. We ended the day by kissing goodbye and didnt really talk much afterwards. She is with the other guy but continues doing this with me. I am truly in love with this girl and am caught in the fence between letting her go for the better of us both or sticking with her through this situation because i know she loves me from the look that you get from that special person that is an undeniable look of love. She also cries and still looks to me for comfort about all her life problems and isnt trying to distance herself from me at all. which is not normal in my eyes.Im not worried about being used because we both made it clear that if i want i can be with someone else. Please help!