I feel like I'm getting my hopes up for nothing but...?

So I had a friend that I really really liked in September. I told her that I liked her and she said that she'd rather stay friends. Well, I was upset but there was nothing I could do so I started to talk less and less to her until we rarely talk anymore and it's just so awkward between us right now. Maybe two months later, she talks to my best friend saying that she really misses me and wants to talk to me but up till now she still hasn't. But today while taking a test (she sits behind me to the left), I noticed that for the most part her body was positioned towards me. After the test, I talked to her a little bit and she seemed very attentive, she smiled a lot and even walked a little closer to talk to me. Also when we see each other anywhere, she looks at me for like three seconds then she looks away. I still like her and I feel like I'm getting my hopes up for nothing...