What does it mean if I still like her? 10 POINTS!?

Two years ago, I had a huge crush on this girl. She was a year younger than me, and I was in 8th grade. We spoke once that year, nothing special. But I grew very attracted to her. 9th grade: I'm in high school, she's in middle school. We never saw each other more than maybe 5 times that year...but somehow I still had a crush on her. 10th grade (this year): the minute I saw her at school, I decided I definitely still liked her. During the homecoming dance (neither of us had dates), I could have sworn she was staring at me the entire time. But after months, I decided it was time to move on. It has been months since I said that (about 6 months actually), and it was working, but she was always in the back of my mind. Yesterday we went to a play, and I sat right next to her. We didn't talk, but somehow I fell for her again. I can't stop thinking about her. I've never liked anyone this long, and have had many crushes this year alone. But she hasn't gone away. Does this mean anything? Any advice to give me?