Infatuated scorpio

Hey everyone,
I see this particular Scorpio man once a year for one month and have been seeing him for three years now. The first year, I was intimidated by him and his intense stare; the second year, I started flirting with him and teasing him a bit. He knew I was very infatuated with him, but he wouldn't do anything about it and I couldn't infer if he was interested or not.
Now for the shocker.......the third year I met him, he would shake every time I was near him! He could barely sit next to me and would breathe heavily every time I got near him. Every time I looked at him, he'd avoid my look (remember, he used to be a starer!)and he'd appear quite shy. He would also make sexually sugestive comments and would act and talk in a very sensual way. What gives for this change of attitude? And if he's interested in me, why will he not call?
How should I proceed with him? I really like him and don't want to loose him or have his interest in me fade.