Ive exactly the same issue, but I’m the guy in this story. I started dating this girl two months back and it’s been wonderful. She’s really been sweet to me and it feels like she really fits with me. We spend the whole weekend last weekend and we the two first days were wonderful. Like we’re really in love. The last day however was very different. It’s like she doesn’t even wanted to be with me. She said she’s losing interest and it’s not because of me or anything i do, but only because of her feelings. I’m really clueless. I guess it’s just how it goes.