Capricorn Female needs some advice.

Well, as the topic title says, I'm a Capricorn woman that could use a little advice from a Scorpio.. Or just anyone that knows a thing or two about love, honestly any help would be fine with me.
For the past eight years I've been attracted to a male Scorpio that I've known since grade school. He's honestly the only person I've met that I've cared so deeply for. It's true what people say about them being extremely magnetic, and I can't break away from him. The problem is, I don't THINK he feels the same, and the other problem is, I can't even tell. Scorpios are incredibly challenging to understand, which is another thing I love about them. So my question is, how do they behave if they've taken an interest into someone? I remember in school last year we had a lot of classes together, and one class in particular he would always playfully tease me and joke around in a charming way. Lately, he's been acting a lot more serious and I see him with lots of different girls he talks to, which of course makes me jealous. I only see him in band class now and on the bus, and whenever I look over to him I sometimes see him staring at me then immediately turning away. Whenever I did talk to him (which was a very few amount of times) I did my best to keep my cool (as Capricorns tend to do) and think very carefully of how I responded to his questions or statements. So our conversations never really lasted.
Anyways, as I said, I just want to know what their behavior is like when they're interested in someone. Or if I completely screwed up somewhere and I should just leave him alone forever, which I'll do if I have to.
Sorry if this was a bit vague but I didn't have much time to type this up, I'd appreciate to hear any answers if you have any, even if it's negative. (Which I have a distinct feeling it will be.)